diff --git a/modules/openapi-generator/src/main/resources/aspnetcore/2.0/controller.mustache b/modules/openapi-generator/src/main/resources/aspnetcore/2.0/controller.mustache
index de15c470d1..a1b1701985 100644
--- a/modules/openapi-generator/src/main/resources/aspnetcore/2.0/controller.mustache
+++ b/modules/openapi-generator/src/main/resources/aspnetcore/2.0/controller.mustache
@@ -23,7 +23,7 @@ namespace {{packageName}}.Controllers
         /// {{#summary}}{{summary}}{{/summary}}
         /// </summary>{{#notes}}
         /// <remarks>{{notes}}</remarks>{{/notes}}{{#allParams}}
-        /// <param name="{{paramName}}">{{description}}</param>{{/allParams}}{{#responses}}
+        /// <param name="{{paramName}}">{{description}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>{{/allParams}}{{#responses}}
         /// <response code="{{code}}">{{message}}</response>{{/responses}}
         [{{httpMethod}}]
         [Route("{{{basePathWithoutHost}}}{{{path}}}")]
@@ -33,6 +33,9 @@ namespace {{packageName}}.Controllers
         [ValidateModelState]{{#useSwashbuckle}}
         [SwaggerOperation("{{operationId}}")]{{#responses}}{{#dataType}}
         [SwaggerResponse(statusCode: {{code}}, type: typeof({{&dataType}}), description: "{{message}}")]{{/dataType}}{{^dataType}}{{/dataType}}{{/responses}}{{/useSwashbuckle}}
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public virtual IActionResult {{operationId}}({{#allParams}}{{>pathParam}}{{>queryParam}}{{>bodyParam}}{{>formParam}}{{>headerParam}}{{^-last}}, {{/-last}}{{/allParams}})
         { {{#responses}}
 {{#dataType}}
diff --git a/modules/openapi-generator/src/main/resources/aspnetcore/2.1/controller.mustache b/modules/openapi-generator/src/main/resources/aspnetcore/2.1/controller.mustache
index 4cc411514c..c8203923b9 100644
--- a/modules/openapi-generator/src/main/resources/aspnetcore/2.1/controller.mustache
+++ b/modules/openapi-generator/src/main/resources/aspnetcore/2.1/controller.mustache
@@ -31,7 +31,7 @@ namespace {{apiPackage}}
         /// {{#summary}}{{summary}}{{/summary}}
         /// </summary>{{#notes}}
         /// <remarks>{{notes}}</remarks>{{/notes}}{{#allParams}}
-        /// <param name="{{paramName}}">{{description}}</param>{{/allParams}}{{#responses}}
+        /// <param name="{{paramName}}">{{description}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>{{/allParams}}{{#responses}}
         /// <response code="{{code}}">{{message}}</response>{{/responses}}
         [{{httpMethod}}]
         [Route("{{{basePathWithoutHost}}}{{{path}}}")]
@@ -50,6 +50,9 @@ namespace {{apiPackage}}
         [SwaggerOperation("{{operationId}}")]{{#responses}}{{#dataType}}
         [SwaggerResponse(statusCode: {{code}}, type: typeof({{&dataType}}), description: "{{message}}")]{{/dataType}}{{^dataType}}{{/dataType}}{{/responses}}{{/useSwashbuckle}}{{^useSwashbuckle}}{{#responses}}{{#dataType}}
         [ProducesResponseType(statusCode: {{code}}, type: typeof({{&dataType}}))]{{/dataType}}{{^dataType}}{{/dataType}}{{/responses}}{{/useSwashbuckle}}
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{operationModifier}} {{#operationResultTask}}{{#operationIsAsync}}async {{/operationIsAsync}}Task<{{/operationResultTask}}IActionResult{{#operationResultTask}}>{{/operationResultTask}} {{operationId}}({{#allParams}}{{>pathParam}}{{>queryParam}}{{>bodyParam}}{{>formParam}}{{>headerParam}}{{^-last}}{{^isCookieParam}}, {{/isCookieParam}}{{/-last}}{{/allParams}}){{^generateBody}};{{/generateBody}}
         {{#generateBody}}
         { 
diff --git a/modules/openapi-generator/src/main/resources/aspnetcore/3.0/controller.mustache b/modules/openapi-generator/src/main/resources/aspnetcore/3.0/controller.mustache
index 9de20cebc1..9f6fcc803d 100644
--- a/modules/openapi-generator/src/main/resources/aspnetcore/3.0/controller.mustache
+++ b/modules/openapi-generator/src/main/resources/aspnetcore/3.0/controller.mustache
@@ -31,7 +31,7 @@ namespace {{apiPackage}}
         /// {{#summary}}{{summary}}{{/summary}}
         /// </summary>{{#notes}}
         /// <remarks>{{notes}}</remarks>{{/notes}}{{#allParams}}
-        /// <param name="{{paramName}}">{{description}}</param>{{/allParams}}{{#responses}}
+        /// <param name="{{paramName}}">{{description}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>{{/allParams}}{{#responses}}
         /// <response code="{{code}}">{{message}}</response>{{/responses}}
         [{{httpMethod}}]
         [Route("{{{basePathWithoutHost}}}{{{path}}}")]
@@ -50,6 +50,9 @@ namespace {{apiPackage}}
         [SwaggerOperation("{{operationId}}")]{{#responses}}{{#dataType}}
         [SwaggerResponse(statusCode: {{code}}, type: typeof({{&dataType}}), description: "{{message}}")]{{/dataType}}{{^dataType}}{{/dataType}}{{/responses}}{{/useSwashbuckle}}{{^useSwashbuckle}}{{#responses}}{{#dataType}}
         [ProducesResponseType(statusCode: {{code}}, type: typeof({{&dataType}}))]{{/dataType}}{{^dataType}}{{/dataType}}{{/responses}}{{/useSwashbuckle}}
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{operationModifier}} {{#operationResultTask}}{{#operationIsAsync}}async {{/operationIsAsync}}Task<{{/operationResultTask}}IActionResult{{#operationResultTask}}>{{/operationResultTask}} {{operationId}}({{#allParams}}{{>pathParam}}{{>queryParam}}{{>bodyParam}}{{>formParam}}{{>headerParam}}{{^-last}}{{^isCookieParam}}, {{/isCookieParam}}{{/-last}}{{/allParams}}){{^generateBody}};{{/generateBody}}
         {{#generateBody}}
         { 
diff --git a/modules/openapi-generator/src/main/resources/csharp-dotnet2/api.mustache b/modules/openapi-generator/src/main/resources/csharp-dotnet2/api.mustache
index cfaf28d4ce..5990a0fbbd 100644
--- a/modules/openapi-generator/src/main/resources/csharp-dotnet2/api.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-dotnet2/api.mustache
@@ -17,8 +17,11 @@ namespace {{apiPackage}}
         /// <summary>
         /// {{summary}} {{notes}}
         /// </summary>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{nickname}} ({{#allParams}}{{{dataType}}} {{paramName}}{{^-last}}, {{/-last}}{{/allParams}});
         {{/operation}}
     }
@@ -80,8 +83,11 @@ namespace {{apiPackage}}
         /// <summary>
         /// {{summary}} {{notes}}
         /// </summary>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{nickname}} ({{#allParams}}{{{dataType}}} {{paramName}}{{^-last}}, {{/-last}}{{/allParams}})
         {
             {{#allParams}}{{#required}}
diff --git a/modules/openapi-generator/src/main/resources/csharp-dotnet2/model.mustache b/modules/openapi-generator/src/main/resources/csharp-dotnet2/model.mustache
index 7c3311e1fd..f9e13ed8f3 100644
--- a/modules/openapi-generator/src/main/resources/csharp-dotnet2/model.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-dotnet2/model.mustache
@@ -21,6 +21,9 @@ namespace {{modelPackage}} {
     /// <value>{{{description}}}</value>{{/description}}
     [DataMember(Name="{{baseName}}", EmitDefaultValue=false)]
     [JsonProperty(PropertyName = "{{baseName}}")]
+    {{#deprecated}}
+    [Obsolete]
+    {{/deprecated}}
     public {{{dataType}}} {{name}} { get; set; }
 
     {{/vars}}
diff --git a/modules/openapi-generator/src/main/resources/csharp-nancyfx/api.mustache b/modules/openapi-generator/src/main/resources/csharp-nancyfx/api.mustache
index 02538ba251..eb34a7fd50 100644
--- a/modules/openapi-generator/src/main/resources/csharp-nancyfx/api.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-nancyfx/api.mustache
@@ -45,8 +45,11 @@ namespace {{packageName}}.{{packageContext}}.Modules
         /// {{notes}}
         /// </summary>
         /// <param name="context">Context of request</param>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#asyncServer}}{{#returnType}}Task<{{{returnType}}}>{{/returnType}}{{^returnType}}Task{{/returnType}}{{/asyncServer}}{{^asyncServer}}{{#returnType}}{{&returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}{{/asyncServer}} {{operationId}}(NancyContext context{{#allParams.0}}, {{/allParams.0}}{{>paramsList}});{{^-last}}
 
         {{/-last}}{{/operation}}
@@ -57,14 +60,16 @@ namespace {{packageName}}.{{packageContext}}.Modules
     /// </summary>
     public abstract class Abstract{{classname}}Service: {{interfacePrefix}}{{classname}}Service
     {
-        {{#operation}}public virtual {{#asyncServer}}{{#returnType}}Task<{{{returnType}}}>{{/returnType}}{{^returnType}}Task{{/returnType}}{{/asyncServer}}{{^asyncServer}}{{#returnType}}{{&returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}{{/asyncServer}} {{operationId}}(NancyContext context{{#allParams.0}}, {{/allParams.0}}{{>paramsList}})
+        {{#operation}}{{#isDeprecated}}[Obsolete]
+        {{/isDeprecated}}public virtual {{#asyncServer}}{{#returnType}}Task<{{{returnType}}}>{{/returnType}}{{^returnType}}Task{{/returnType}}{{/asyncServer}}{{^asyncServer}}{{#returnType}}{{&returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}{{/asyncServer}} {{operationId}}(NancyContext context{{#allParams.0}}, {{/allParams.0}}{{>paramsList}})
         {
             {{^asyncServer}}{{#returnType}}return {{/returnType}}{{/asyncServer}}{{#asyncServer}}return {{/asyncServer}}{{operationId}}({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}});
         }{{^-last}}
 
         {{/-last}}{{/operation}}
 
-        {{#operation}}protected abstract {{#asyncServer}}{{#returnType}}Task<{{{returnType}}}>{{/returnType}}{{^returnType}}Task{{/returnType}}{{/asyncServer}}{{^asyncServer}}{{#returnType}}{{&returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}{{/asyncServer}} {{operationId}}({{>paramsList}});{{^-last}}
+        {{#operation}}{{#isDeprecated}}[Obsolete]
+        {{/isDeprecated}}protected abstract {{#asyncServer}}{{#returnType}}Task<{{{returnType}}}>{{/returnType}}{{^returnType}}Task{{/returnType}}{{/asyncServer}}{{^asyncServer}}{{#returnType}}{{&returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}{{/asyncServer}} {{operationId}}({{>paramsList}});{{^-last}}
 
         {{/-last}}{{/operation}}
     }
diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/api.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/api.mustache
index 8d84eecefb..bb4894411b 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/api.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/api.mustache
@@ -30,8 +30,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// </remarks>
         {{/notes}}
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{operationId}}({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}});
 
         /// <summary>
@@ -41,8 +44,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{notes}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>ApiResponse of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}Object(void){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}> {{operationId}}WithHttpInfo({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}});
         {{/operation}}
         #endregion Synchronous Operations
@@ -64,10 +70,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}System.Threading.Tasks.Task<{{{returnType}}}>{{/returnType}}{{^returnType}}System.Threading.Tasks.Task{{/returnType}} {{operationId}}Async({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -78,10 +87,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse{{#returnType}} ({{returnType}}){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         System.Threading.Tasks.Task<ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>> {{operationId}}WithHttpInfoAsync({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         {{/operation}}
         #endregion Asynchronous Operations
@@ -220,8 +232,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{operationId}}({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}})
         {
             {{#returnType}}{{packageName}}.Client.ApiResponse<{{{returnType}}}> localVarResponse = {{operationId}}WithHttpInfo({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}});
@@ -232,8 +247,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>ApiResponse of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}Object(void){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{packageName}}.Client.ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}> {{operationId}}WithHttpInfo({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}})
         {
             {{#allParams}}
@@ -429,10 +447,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}public async System.Threading.Tasks.Task<{{{returnType}}}>{{/returnType}}{{^returnType}}public async System.Threading.Tasks.Task{{/returnType}} {{operationId}}Async({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             {{#returnType}}{{packageName}}.Client.ApiResponse<{{{returnType}}}> localVarResponse = await {{operationId}}WithHttpInfoAsync({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}cancellationToken).ConfigureAwait(false);
@@ -444,10 +465,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse{{#returnType}} ({{returnType}}){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public async System.Threading.Tasks.Task<{{packageName}}.Client.ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>> {{operationId}}WithHttpInfoAsync({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             {{#allParams}}
diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/libraries/httpclient/api.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/libraries/httpclient/api.mustache
index 20ddfe96b9..bf3e437799 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/libraries/httpclient/api.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/libraries/httpclient/api.mustache
@@ -31,8 +31,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// </remarks>
         {{/notes}}
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{operationId}}({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}});
 
         /// <summary>
@@ -42,8 +45,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{notes}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>ApiResponse of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}Object(void){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}> {{operationId}}WithHttpInfo({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}});
         {{/operation}}
         #endregion Synchronous Operations
@@ -65,10 +71,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}System.Threading.Tasks.Task<{{{returnType}}}>{{/returnType}}{{^returnType}}System.Threading.Tasks.Task{{/returnType}} {{operationId}}Async({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -79,10 +88,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse{{#returnType}} ({{returnType}}){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         System.Threading.Tasks.Task<ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>> {{operationId}}WithHttpInfoAsync({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         {{/operation}}
         #endregion Asynchronous Operations
@@ -318,8 +330,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{operationId}}({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}})
         {
             {{#returnType}}{{packageName}}.Client.ApiResponse<{{{returnType}}}> localVarResponse = {{operationId}}WithHttpInfo({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}});
@@ -330,8 +345,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>ApiResponse of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}Object(void){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{packageName}}.Client.ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}> {{operationId}}WithHttpInfo({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}})
         {
             {{#allParams}}
@@ -527,10 +545,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}public async System.Threading.Tasks.Task<{{{returnType}}}>{{/returnType}}{{^returnType}}public async System.Threading.Tasks.Task{{/returnType}} {{operationId}}Async({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             {{#returnType}}{{packageName}}.Client.ApiResponse<{{{returnType}}}> localVarResponse = await {{operationId}}WithHttpInfoAsync({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}cancellationToken).ConfigureAwait(false);
@@ -542,10 +563,13 @@ namespace {{packageName}}.{{apiPackage}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
         {{#allParams}}
-        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        /// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse{{#returnType}} ({{returnType}}){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public async System.Threading.Tasks.Task<{{packageName}}.Client.ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>> {{operationId}}WithHttpInfoAsync({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             {{#allParams}}
diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/modelGeneric.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/modelGeneric.mustache
index 6eb1a2359d..ad65a3b836 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/modelGeneric.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/modelGeneric.mustache
@@ -33,6 +33,9 @@
         {{/description}}
         {{^conditionalSerialization}}
         [DataMember(Name = "{{baseName}}"{{#required}}, IsRequired = true{{/required}}, EmitDefaultValue = {{#vendorExtensions.x-emit-default-value}}true{{/vendorExtensions.x-emit-default-value}}{{^vendorExtensions.x-emit-default-value}}{{#isBoolean}}true{{/isBoolean}}{{^isBoolean}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}false{{/isNullable}}{{/isBoolean}}{{/vendorExtensions.x-emit-default-value}})]
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{#complexType}}{{{complexType}}}{{/complexType}}{{^complexType}}{{{datatypeWithEnum}}}{{/complexType}}{{^isContainer}}{{^required}}?{{/required}}{{/isContainer}} {{name}} { get; set; }
         {{#isReadOnly}}
 
@@ -49,6 +52,9 @@
         {{#conditionalSerialization}}
         {{#isReadOnly}}
         [DataMember(Name = "{{baseName}}"{{#required}}, IsRequired = true{{/required}}, EmitDefaultValue = {{#vendorExtensions.x-emit-default-value}}true{{/vendorExtensions.x-emit-default-value}}{{^vendorExtensions.x-emit-default-value}}{{#isBoolean}}true{{/isBoolean}}{{^isBoolean}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}false{{/isNullable}}{{/isBoolean}}{{/vendorExtensions.x-emit-default-value}})]
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{#complexType}}{{{complexType}}}{{/complexType}}{{^complexType}}{{{datatypeWithEnum}}}{{/complexType}}{{^isContainer}}{{^required}}?{{/required}}{{/isContainer}} {{name}} { get; set; }
         
 
@@ -64,6 +70,9 @@
         
         {{^isReadOnly}}
         [DataMember(Name = "{{baseName}}"{{#required}}, IsRequired = true{{/required}}, EmitDefaultValue = {{#vendorExtensions.x-emit-default-value}}true{{/vendorExtensions.x-emit-default-value}}{{^vendorExtensions.x-emit-default-value}}{{#isBoolean}}true{{/isBoolean}}{{^isBoolean}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}false{{/isNullable}}{{/isBoolean}}{{/vendorExtensions.x-emit-default-value}})]
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{#complexType}}{{{complexType}}}{{/complexType}}{{^complexType}}{{{datatypeWithEnum}}}{{/complexType}}{{^isContainer}}{{^required}}?{{/required}}{{/isContainer}} {{name}} 
         { 
             get{ return _{{name}};}
@@ -184,6 +193,9 @@
         {{#isDate}}
         [JsonConverter(typeof(OpenAPIDateConverter))]
         {{/isDate}}
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{{dataType}}} {{name}} { get; {{#isReadOnly}}private {{/isReadOnly}}set; }
 
         {{#isReadOnly}}
@@ -203,6 +215,9 @@
         {{#isDate}}
         [JsonConverter(typeof(OpenAPIDateConverter))]
         {{/isDate}}
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{{dataType}}} {{name}} { get; private set; }
         
         /// <summary>
@@ -219,6 +234,9 @@
         [JsonConverter(typeof(OpenAPIDateConverter))]
         {{/isDate}}
         [DataMember(Name = "{{baseName}}"{{#required}}, IsRequired = true{{/required}}, EmitDefaultValue = {{#vendorExtensions.x-emit-default-value}}true{{/vendorExtensions.x-emit-default-value}}{{^vendorExtensions.x-emit-default-value}}{{#isBoolean}}true{{/isBoolean}}{{^isBoolean}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}false{{/isNullable}}{{/isBoolean}}{{/vendorExtensions.x-emit-default-value}})]
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{{dataType}}} {{name}}
         { 
             get{ return _{{name}};}
diff --git a/modules/openapi-generator/src/main/resources/csharp/api.mustache b/modules/openapi-generator/src/main/resources/csharp/api.mustache
index 700d2bdb2b..8e80b857ad 100644
--- a/modules/openapi-generator/src/main/resources/csharp/api.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp/api.mustache
@@ -31,8 +31,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{notes}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{operationId}} ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}});
 
         /// <summary>
@@ -42,8 +45,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{notes}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>ApiResponse of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}Object(void){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}> {{operationId}}WithHttpInfo ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}});
         {{/operation}}
         #endregion Synchronous Operations
@@ -57,9 +63,12 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{notes}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}System.Threading.Tasks.Task<{{{returnType}}}>{{/returnType}}{{^returnType}}System.Threading.Tasks.Task{{/returnType}} {{operationId}}Async ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
@@ -69,9 +78,12 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{notes}}
         /// </remarks>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse{{#returnType}} ({{returnType}}){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         System.Threading.Tasks.Task<ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>> {{operationId}}WithHttpInfoAsync ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}CancellationToken cancellationToken = default(CancellationToken));
         {{/operation}}
         #endregion Asynchronous Operations
@@ -191,8 +203,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>{{#returnType}}{{returnType}}{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{operationId}} ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}})
         {
              {{#returnType}}ApiResponse<{{{returnType}}}> localVarResponse = {{operationId}}WithHttpInfo({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}});
@@ -203,8 +218,11 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <returns>ApiResponse of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}Object(void){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}> {{operationId}}WithHttpInfo ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}})
         {
             {{#allParams}}
@@ -335,9 +353,12 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of {{#returnType}}{{returnType}}{{/returnType}}{{^returnType}}void{{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         {{#returnType}}public async System.Threading.Tasks.Task<{{{returnType}}}>{{/returnType}}{{^returnType}}public async System.Threading.Tasks.Task{{/returnType}} {{operationId}}Async ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}CancellationToken cancellationToken = default(CancellationToken))
         {
              {{#returnType}}ApiResponse<{{{returnType}}}> localVarResponse = await {{operationId}}WithHttpInfoAsync({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}cancellationToken);
@@ -349,9 +370,12 @@ namespace {{packageName}}.{{apiPackage}}
         /// {{summary}} {{notes}}
         /// </summary>
         /// <exception cref="{{packageName}}.Client.ApiException">Thrown when fails to make API call</exception>
-        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}</param>
+        {{#allParams}}/// <param name="{{paramName}}">{{description}}{{^required}} (optional{{#defaultValue}}, default to {{.}}{{/defaultValue}}){{/required}}{{#isDeprecated}} (deprecated){{/isDeprecated}}</param>
         {{/allParams}}/// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse{{#returnType}} ({{returnType}}){{/returnType}}</returns>
+        {{#isDeprecated}}
+        [Obsolete]
+        {{/isDeprecated}}
         public async System.Threading.Tasks.Task<ApiResponse<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>> {{operationId}}WithHttpInfoAsync ({{#allParams}}{{{dataType}}} {{paramName}}{{^required}}{{#optionalMethodArgument}} = default({{{dataType}}}){{/optionalMethodArgument}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}}{{#allParams.0}}, {{/allParams.0}}CancellationToken cancellationToken = default(CancellationToken))
         {
             {{#allParams}}
diff --git a/modules/openapi-generator/src/main/resources/csharp/modelGeneric.mustache b/modules/openapi-generator/src/main/resources/csharp/modelGeneric.mustache
index b2077256ff..933ba0824a 100644
--- a/modules/openapi-generator/src/main/resources/csharp/modelGeneric.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp/modelGeneric.mustache
@@ -32,6 +32,9 @@
         /// <value>{{description}}</value>
         {{/description}}
         [DataMember(Name="{{baseName}}", EmitDefaultValue={{#vendorExtensions.x-emit-default-value}}true{{/vendorExtensions.x-emit-default-value}}{{^vendorExtensions.x-emit-default-value}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}{{#required}}true{{/required}}{{^required}}false{{/required}}{{/isNullable}}{{/vendorExtensions.x-emit-default-value}})]
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{#complexType}}{{{complexType}}}{{/complexType}}{{^complexType}}{{{datatypeWithEnum}}}{{/complexType}}{{^isContainer}}{{^required}}?{{/required}}{{/isContainer}} {{name}} { get; set; }
         {{/isEnum}}
         {{/vars}}
@@ -110,6 +113,9 @@ this.{{name}} = {{#lambda.camelcase_param}}{{name}}{{/lambda.camelcase_param}};
         /// <value>{{description}}</value>{{/description}}
         [DataMember(Name="{{baseName}}", EmitDefaultValue={{#vendorExtensions.x-emit-default-value}}true{{/vendorExtensions.x-emit-default-value}}{{^vendorExtensions.x-emit-default-value}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}{{#required}}true{{/required}}{{^required}}false{{/required}}{{/isNullable}}{{/vendorExtensions.x-emit-default-value}})]{{#isDate}}
         [JsonConverter(typeof(OpenAPIDateConverter))]{{/isDate}}
+        {{#deprecated}}
+        [Obsolete]
+        {{/deprecated}}
         public {{{dataType}}} {{name}} { get; {{#isReadOnly}}private {{/isReadOnly}}set; }
         {{/isEnum}}
         {{/isInherited}}
diff --git a/modules/openapi-generator/src/test/resources/3_0/java/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml b/modules/openapi-generator/src/test/resources/3_0/java/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
index a2fbd151bf..74c5926c22 100644
--- a/modules/openapi-generator/src/test/resources/3_0/java/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/java/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
@@ -83,6 +83,7 @@ paths:
           required: true
           style: form
           explode: false
+          deprecated: true
           schema:
             type: array
             items:
diff --git a/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml b/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml
index 7502a2db60..b5b6109644 100644
--- a/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml
@@ -85,6 +85,7 @@ paths:
           required: true
           style: form
           explode: false
+          deprecated: true
           schema:
             type: array
             items:
diff --git a/samples/client/petstore/csharp-dotnet2/OpenAPIClientTest/Lib/OpenAPIClient/src/main/CsharpDotNet2/Org/OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-dotnet2/OpenAPIClientTest/Lib/OpenAPIClient/src/main/CsharpDotNet2/Org/OpenAPITools/Api/PetApi.cs
index 48b1119b50..7a6131e249 100644
--- a/samples/client/petstore/csharp-dotnet2/OpenAPIClientTest/Lib/OpenAPIClient/src/main/CsharpDotNet2/Org/OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-dotnet2/OpenAPIClientTest/Lib/OpenAPIClient/src/main/CsharpDotNet2/Org/OpenAPITools/Api/PetApi.cs
@@ -35,6 +35,7 @@ namespace Org.OpenAPITools.Api
         /// </summary>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags (List<string> tags);
         /// <summary>
         /// Find pet by ID Returns a single pet
@@ -237,6 +238,7 @@ namespace Org.OpenAPITools.Api
         /// </summary>
         /// <param name="tags">Tags to filter by</param> 
         /// <returns>List&lt;Pet&gt;</returns>            
+        [Obsolete]
         public List<Pet> FindPetsByTags (List<string> tags)
         {
             
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Api/PetApi.cs
index 2bf19af1b1..d73282dfca 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Api/PetApi.cs
@@ -71,7 +71,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus(List<string> status);
 
@@ -82,7 +82,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status);
         /// <summary>
@@ -94,6 +94,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(List<string> tags);
 
         /// <summary>
@@ -105,6 +106,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -275,7 +277,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -287,7 +289,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -301,6 +303,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -313,6 +316,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -851,7 +855,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus(List<string> status)
         {
@@ -863,7 +867,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status)
         {
@@ -929,7 +933,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -942,7 +946,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -1014,6 +1018,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags(List<string> tags)
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1026,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1093,6 +1099,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken).ConfigureAwait(false);
@@ -1106,6 +1113,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
index 55881e301d..d07754cd2e 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
@@ -76,6 +76,7 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Id
         /// </summary>
         [DataMember(Name = "id", EmitDefaultValue = false)]
+        [Obsolete]
         public decimal Id
         { 
             get{ return _Id;}
@@ -100,6 +101,7 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets DeprecatedRef
         /// </summary>
         [DataMember(Name = "deprecatedRef", EmitDefaultValue = false)]
+        [Obsolete]
         public DeprecatedObject DeprecatedRef
         { 
             get{ return _DeprecatedRef;}
@@ -124,6 +126,7 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Bars
         /// </summary>
         [DataMember(Name = "bars", EmitDefaultValue = false)]
+        [Obsolete]
         public List<string> Bars
         { 
             get{ return _Bars;}
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Api/PetApi.cs
index f835c81b4d..0aba26f224 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Api/PetApi.cs
@@ -72,7 +72,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus(List<string> status);
 
@@ -83,7 +83,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status);
         /// <summary>
@@ -95,6 +95,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(List<string> tags);
 
         /// <summary>
@@ -106,6 +107,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -276,7 +278,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -288,7 +290,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -302,6 +304,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -314,6 +317,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -945,7 +949,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus(List<string> status)
         {
@@ -957,7 +961,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status)
         {
@@ -1023,7 +1027,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -1036,7 +1040,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -1108,6 +1112,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags(List<string> tags)
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1120,6 +1125,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1187,6 +1193,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken).ConfigureAwait(false);
@@ -1200,6 +1207,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
index 8872961b5d..57ba9112b1 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
@@ -59,18 +59,21 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Id
         /// </summary>
         [DataMember(Name = "id", EmitDefaultValue = false)]
+        [Obsolete]
         public decimal Id { get; set; }
 
         /// <summary>
         /// Gets or Sets DeprecatedRef
         /// </summary>
         [DataMember(Name = "deprecatedRef", EmitDefaultValue = false)]
+        [Obsolete]
         public DeprecatedObject DeprecatedRef { get; set; }
 
         /// <summary>
         /// Gets or Sets Bars
         /// </summary>
         [DataMember(Name = "bars", EmitDefaultValue = false)]
+        [Obsolete]
         public List<string> Bars { get; set; }
 
         /// <summary>
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Api/PetApi.cs
index 2bf19af1b1..d73282dfca 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Api/PetApi.cs
@@ -71,7 +71,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus(List<string> status);
 
@@ -82,7 +82,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status);
         /// <summary>
@@ -94,6 +94,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(List<string> tags);
 
         /// <summary>
@@ -105,6 +106,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -275,7 +277,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -287,7 +289,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -301,6 +303,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -313,6 +316,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -851,7 +855,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus(List<string> status)
         {
@@ -863,7 +867,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status)
         {
@@ -929,7 +933,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -942,7 +946,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -1014,6 +1018,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags(List<string> tags)
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1026,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1093,6 +1099,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken).ConfigureAwait(false);
@@ -1106,6 +1113,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
index a64ef652be..25b5758c91 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
@@ -58,18 +58,21 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Id
         /// </summary>
         [DataMember(Name = "id", EmitDefaultValue = false)]
+        [Obsolete]
         public decimal Id { get; set; }
 
         /// <summary>
         /// Gets or Sets DeprecatedRef
         /// </summary>
         [DataMember(Name = "deprecatedRef", EmitDefaultValue = false)]
+        [Obsolete]
         public DeprecatedObject DeprecatedRef { get; set; }
 
         /// <summary>
         /// Gets or Sets Bars
         /// </summary>
         [DataMember(Name = "bars", EmitDefaultValue = false)]
+        [Obsolete]
         public List<string> Bars { get; set; }
 
         /// <summary>
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Api/PetApi.cs
index 2bf19af1b1..d73282dfca 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Api/PetApi.cs
@@ -71,7 +71,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus(List<string> status);
 
@@ -82,7 +82,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status);
         /// <summary>
@@ -94,6 +94,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(List<string> tags);
 
         /// <summary>
@@ -105,6 +106,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -275,7 +277,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -287,7 +289,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -301,6 +303,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -313,6 +316,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -851,7 +855,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus(List<string> status)
         {
@@ -863,7 +867,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status)
         {
@@ -929,7 +933,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -942,7 +946,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -1014,6 +1018,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags(List<string> tags)
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1026,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1093,6 +1099,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken).ConfigureAwait(false);
@@ -1106,6 +1113,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
index a64ef652be..25b5758c91 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
@@ -58,18 +58,21 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Id
         /// </summary>
         [DataMember(Name = "id", EmitDefaultValue = false)]
+        [Obsolete]
         public decimal Id { get; set; }
 
         /// <summary>
         /// Gets or Sets DeprecatedRef
         /// </summary>
         [DataMember(Name = "deprecatedRef", EmitDefaultValue = false)]
+        [Obsolete]
         public DeprecatedObject DeprecatedRef { get; set; }
 
         /// <summary>
         /// Gets or Sets Bars
         /// </summary>
         [DataMember(Name = "bars", EmitDefaultValue = false)]
+        [Obsolete]
         public List<string> Bars { get; set; }
 
         /// <summary>
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs
index 2bf19af1b1..d73282dfca 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs
@@ -71,7 +71,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus(List<string> status);
 
@@ -82,7 +82,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status);
         /// <summary>
@@ -94,6 +94,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(List<string> tags);
 
         /// <summary>
@@ -105,6 +106,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -275,7 +277,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -287,7 +289,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -301,6 +303,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -313,6 +316,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -851,7 +855,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus(List<string> status)
         {
@@ -863,7 +867,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status)
         {
@@ -929,7 +933,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -942,7 +946,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -1014,6 +1018,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags(List<string> tags)
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1026,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1093,6 +1099,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken).ConfigureAwait(false);
@@ -1106,6 +1113,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
index a64ef652be..25b5758c91 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
@@ -58,18 +58,21 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Id
         /// </summary>
         [DataMember(Name = "id", EmitDefaultValue = false)]
+        [Obsolete]
         public decimal Id { get; set; }
 
         /// <summary>
         /// Gets or Sets DeprecatedRef
         /// </summary>
         [DataMember(Name = "deprecatedRef", EmitDefaultValue = false)]
+        [Obsolete]
         public DeprecatedObject DeprecatedRef { get; set; }
 
         /// <summary>
         /// Gets or Sets Bars
         /// </summary>
         [DataMember(Name = "bars", EmitDefaultValue = false)]
+        [Obsolete]
         public List<string> Bars { get; set; }
 
         /// <summary>
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Api/PetApi.cs
index 2bf19af1b1..d73282dfca 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Api/PetApi.cs
@@ -71,7 +71,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus(List<string> status);
 
@@ -82,7 +82,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status);
         /// <summary>
@@ -94,6 +94,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(List<string> tags);
 
         /// <summary>
@@ -105,6 +106,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -275,7 +277,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -287,7 +289,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -301,6 +303,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -313,6 +316,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -851,7 +855,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus(List<string> status)
         {
@@ -863,7 +867,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status)
         {
@@ -929,7 +933,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -942,7 +946,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -1014,6 +1018,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags(List<string> tags)
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1026,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1093,6 +1099,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken).ConfigureAwait(false);
@@ -1106,6 +1113,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
index 3a3ce4c580..33f85eacd4 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
@@ -57,18 +57,21 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Id
         /// </summary>
         [DataMember(Name = "id", EmitDefaultValue = false)]
+        [Obsolete]
         public decimal Id { get; set; }
 
         /// <summary>
         /// Gets or Sets DeprecatedRef
         /// </summary>
         [DataMember(Name = "deprecatedRef", EmitDefaultValue = false)]
+        [Obsolete]
         public DeprecatedObject DeprecatedRef { get; set; }
 
         /// <summary>
         /// Gets or Sets Bars
         /// </summary>
         [DataMember(Name = "bars", EmitDefaultValue = false)]
+        [Obsolete]
         public List<string> Bars { get; set; }
 
         /// <summary>
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Api/PetApi.cs
index 82f8266d4a..6f8809911e 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Api/PetApi.cs
@@ -71,7 +71,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus(List<string> status);
 
@@ -82,7 +82,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status);
         /// <summary>
@@ -94,6 +94,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(List<string> tags);
 
         /// <summary>
@@ -105,6 +106,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -253,7 +255,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -265,7 +267,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -279,6 +281,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
 
         /// <summary>
@@ -291,6 +294,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -776,7 +780,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus(List<string> status)
         {
@@ -788,7 +792,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo(List<string> status)
         {
@@ -838,7 +842,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -851,7 +855,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync(List<string> status, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
@@ -907,6 +911,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags(List<string> tags)
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -919,6 +924,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public Org.OpenAPITools.Client.ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo(List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -970,6 +976,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             Org.OpenAPITools.Client.ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken).ConfigureAwait(false);
@@ -983,6 +990,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel the request.</param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<Org.OpenAPITools.Client.ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync(List<string> tags, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Model/Pet.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Model/Pet.cs
index 6048e68c2b..beb04e50af 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Model/Pet.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCoreAndNet47/src/Org.OpenAPITools/Model/Pet.cs
@@ -65,6 +65,7 @@ namespace Org.OpenAPITools.Model
         /// </summary>
         /// <value>pet status in the store</value>
         [DataMember(Name = "status", EmitDefaultValue = false)]
+        [Obsolete]
         public StatusEnum? Status { get; set; }
         /// <summary>
         /// Initializes a new instance of the <see cref="Pet" /> class.
diff --git a/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs
index 4a0b50d0cb..af3d41b729 100644
--- a/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Api/PetApi.cs
@@ -76,7 +76,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         List<Pet> FindPetsByStatus (List<string> status);
 
@@ -87,7 +87,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo (List<string> status);
         /// <summary>
@@ -99,6 +99,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags (List<string> tags);
 
         /// <summary>
@@ -110,6 +111,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -285,7 +287,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync (List<string> status, CancellationToken cancellationToken = default(CancellationToken));
@@ -297,7 +299,7 @@ namespace Org.OpenAPITools.Api
         /// Multiple status values can be provided with comma separated strings
         /// </remarks>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync (List<string> status, CancellationToken cancellationToken = default(CancellationToken));
@@ -311,6 +313,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
@@ -323,6 +326,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -876,7 +880,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>List&lt;Pet&gt;</returns>
         public List<Pet> FindPetsByStatus (List<string> status)
         {
@@ -888,7 +892,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
         public ApiResponse<List<Pet>> FindPetsByStatusWithHttpInfo (List<string> status)
         {
@@ -949,7 +953,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByStatusAsync (List<string> status, CancellationToken cancellationToken = default(CancellationToken))
@@ -963,7 +967,7 @@ namespace Org.OpenAPITools.Api
         /// Finds Pets by status Multiple status values can be provided with comma separated strings
         /// </summary>
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
         public async System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByStatusWithHttpInfoAsync (List<string> status, CancellationToken cancellationToken = default(CancellationToken))
@@ -1027,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags (List<string> tags)
         {
              ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1039,6 +1044,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1101,6 +1107,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
              ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken);
@@ -1115,6 +1122,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs b/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
index ec7b5c5193..259253c2f7 100644
--- a/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
+++ b/samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Model/ObjectWithDeprecatedFields.cs
@@ -55,18 +55,21 @@ namespace Org.OpenAPITools.Model
         /// Gets or Sets Id
         /// </summary>
         [DataMember(Name="id", EmitDefaultValue=false)]
+        [Obsolete]
         public decimal Id { get; set; }
 
         /// <summary>
         /// Gets or Sets DeprecatedRef
         /// </summary>
         [DataMember(Name="deprecatedRef", EmitDefaultValue=false)]
+        [Obsolete]
         public DeprecatedObject DeprecatedRef { get; set; }
 
         /// <summary>
         /// Gets or Sets Bars
         /// </summary>
         [DataMember(Name="bars", EmitDefaultValue=false)]
+        [Obsolete]
         public List<string> Bars { get; set; }
 
         /// <summary>
diff --git a/samples/client/petstore/csharp/OpenAPIClientNet35/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp/OpenAPIClientNet35/src/Org.OpenAPITools/Api/PetApi.cs
index ae5770045e..186ed1237e 100644
--- a/samples/client/petstore/csharp/OpenAPIClientNet35/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp/OpenAPIClientNet35/src/Org.OpenAPITools/Api/PetApi.cs
@@ -99,6 +99,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags (List<string> tags);
 
         /// <summary>
@@ -110,6 +111,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -570,6 +572,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags (List<string> tags)
         {
              ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -582,6 +585,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags)
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp/OpenAPIClientNet40/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp/OpenAPIClientNet40/src/Org.OpenAPITools/Api/PetApi.cs
index 4bd7fec789..07a049f28c 100644
--- a/samples/client/petstore/csharp/OpenAPIClientNet40/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp/OpenAPIClientNet40/src/Org.OpenAPITools/Api/PetApi.cs
@@ -99,6 +99,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags (List<string> tags);
 
         /// <summary>
@@ -110,6 +111,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -570,6 +572,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags (List<string> tags)
         {
              ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -582,6 +585,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags)
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp/OpenAPIClientNetCoreProject/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp/OpenAPIClientNetCoreProject/src/Org.OpenAPITools/Api/PetApi.cs
index 851379ebc9..300293b4c4 100644
--- a/samples/client/petstore/csharp/OpenAPIClientNetCoreProject/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp/OpenAPIClientNetCoreProject/src/Org.OpenAPITools/Api/PetApi.cs
@@ -99,6 +99,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags (List<string> tags);
 
         /// <summary>
@@ -110,6 +111,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -311,6 +313,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
@@ -323,6 +326,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -1027,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags (List<string> tags)
         {
              ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1039,6 +1044,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1101,6 +1107,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
              ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken);
@@ -1115,6 +1122,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp/OpenAPIClientNetStandard/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp/OpenAPIClientNetStandard/src/Org.OpenAPITools/Api/PetApi.cs
index 851379ebc9..300293b4c4 100644
--- a/samples/client/petstore/csharp/OpenAPIClientNetStandard/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp/OpenAPIClientNetStandard/src/Org.OpenAPITools/Api/PetApi.cs
@@ -99,6 +99,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags (List<string> tags);
 
         /// <summary>
@@ -110,6 +111,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -311,6 +313,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
@@ -323,6 +326,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -1027,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags (List<string> tags)
         {
              ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1039,6 +1044,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1101,6 +1107,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
              ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken);
@@ -1115,6 +1122,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/csharp/OpenAPIClientWithPropertyChanged/src/Org.OpenAPITools/Api/PetApi.cs b/samples/client/petstore/csharp/OpenAPIClientWithPropertyChanged/src/Org.OpenAPITools/Api/PetApi.cs
index 0f65ea2d80..223e05ce52 100644
--- a/samples/client/petstore/csharp/OpenAPIClientWithPropertyChanged/src/Org.OpenAPITools/Api/PetApi.cs
+++ b/samples/client/petstore/csharp/OpenAPIClientWithPropertyChanged/src/Org.OpenAPITools/Api/PetApi.cs
@@ -99,6 +99,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags (List<string> tags);
 
         /// <summary>
@@ -110,6 +111,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags);
         /// <summary>
         /// Find pet by ID
@@ -311,6 +313,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
@@ -323,6 +326,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken));
         /// <summary>
         /// Find pet by ID
@@ -1027,6 +1031,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         public List<Pet> FindPetsByTags (List<string> tags)
         {
              ApiResponse<List<Pet>> localVarResponse = FindPetsByTagsWithHttpInfo(tags);
@@ -1039,6 +1044,7 @@ namespace Org.OpenAPITools.Api
         /// <exception cref="Org.OpenAPITools.Client.ApiException">Thrown when fails to make API call</exception>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>ApiResponse of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public ApiResponse<List<Pet>> FindPetsByTagsWithHttpInfo (List<string> tags)
         {
             // verify the required parameter 'tags' is set
@@ -1101,6 +1107,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of List&lt;Pet&gt;</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<List<Pet>> FindPetsByTagsAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
              ApiResponse<List<Pet>> localVarResponse = await FindPetsByTagsWithHttpInfoAsync(tags, cancellationToken);
@@ -1115,6 +1122,7 @@ namespace Org.OpenAPITools.Api
         /// <param name="tags">Tags to filter by</param>
         /// <param name="cancellationToken">Cancellation Token to cancel request (optional) </param>
         /// <returns>Task of ApiResponse (List&lt;Pet&gt;)</returns>
+        [Obsolete]
         public async System.Threading.Tasks.Task<ApiResponse<List<Pet>>> FindPetsByTagsWithHttpInfoAsync (List<string> tags, CancellationToken cancellationToken = default(CancellationToken))
         {
             // verify the required parameter 'tags' is set
diff --git a/samples/client/petstore/java/feign/api/openapi.yaml b/samples/client/petstore/java/feign/api/openapi.yaml
index baf5bb3cde..9c33abbfda 100644
--- a/samples/client/petstore/java/feign/api/openapi.yaml
+++ b/samples/client/petstore/java/feign/api/openapi.yaml
@@ -100,7 +100,8 @@ paths:
       description: Multiple status values can be provided with comma separated strings
       operationId: findPetsByStatus
       parameters:
-      - description: Status values that need to be considered for filter
+      - deprecated: true
+        description: Status values that need to be considered for filter
         explode: false
         in: query
         name: status
diff --git a/samples/client/petstore/java/webclient/api/openapi.yaml b/samples/client/petstore/java/webclient/api/openapi.yaml
index baf5bb3cde..9c33abbfda 100644
--- a/samples/client/petstore/java/webclient/api/openapi.yaml
+++ b/samples/client/petstore/java/webclient/api/openapi.yaml
@@ -100,7 +100,8 @@ paths:
       description: Multiple status values can be provided with comma separated strings
       operationId: findPetsByStatus
       parameters:
-      - description: Status values that need to be considered for filter
+      - deprecated: true
+        description: Status values that need to be considered for filter
         explode: false
         in: query
         name: status
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8/api/openapi.yaml b/samples/openapi3/client/petstore/java/jersey2-java8/api/openapi.yaml
index 235093bf19..db6c6af841 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8/api/openapi.yaml
+++ b/samples/openapi3/client/petstore/java/jersey2-java8/api/openapi.yaml
@@ -98,7 +98,8 @@ paths:
       description: Multiple status values can be provided with comma separated strings
       operationId: findPetsByStatus
       parameters:
-      - description: Status values that need to be considered for filter
+      - deprecated: true
+        description: Status values that need to be considered for filter
         explode: false
         in: query
         name: status
diff --git a/samples/server/petstore/aspnetcore-3.0/src/Org.OpenAPITools/Controllers/PetApi.cs b/samples/server/petstore/aspnetcore-3.0/src/Org.OpenAPITools/Controllers/PetApi.cs
index d58ff968d3..e23c800b82 100644
--- a/samples/server/petstore/aspnetcore-3.0/src/Org.OpenAPITools/Controllers/PetApi.cs
+++ b/samples/server/petstore/aspnetcore-3.0/src/Org.OpenAPITools/Controllers/PetApi.cs
@@ -108,6 +108,7 @@ namespace Org.OpenAPITools.Controllers
         [ValidateModelState]
         [SwaggerOperation("FindPetsByTags")]
         [SwaggerResponse(statusCode: 200, type: typeof(List<Pet>), description: "successful operation")]
+        [Obsolete]
         public virtual IActionResult FindPetsByTags([FromQuery (Name = "tags")][Required()]List<string> tags)
         { 
 
diff --git a/samples/server/petstore/aspnetcore-3.1/src/Org.OpenAPITools/Controllers/PetApi.cs b/samples/server/petstore/aspnetcore-3.1/src/Org.OpenAPITools/Controllers/PetApi.cs
index d58ff968d3..e23c800b82 100644
--- a/samples/server/petstore/aspnetcore-3.1/src/Org.OpenAPITools/Controllers/PetApi.cs
+++ b/samples/server/petstore/aspnetcore-3.1/src/Org.OpenAPITools/Controllers/PetApi.cs
@@ -108,6 +108,7 @@ namespace Org.OpenAPITools.Controllers
         [ValidateModelState]
         [SwaggerOperation("FindPetsByTags")]
         [SwaggerResponse(statusCode: 200, type: typeof(List<Pet>), description: "successful operation")]
+        [Obsolete]
         public virtual IActionResult FindPetsByTags([FromQuery (Name = "tags")][Required()]List<string> tags)
         { 
 
diff --git a/samples/server/petstore/aspnetcore-5.0/src/Org.OpenAPITools/Controllers/PetApi.cs b/samples/server/petstore/aspnetcore-5.0/src/Org.OpenAPITools/Controllers/PetApi.cs
index 3162f82261..68541eb890 100644
--- a/samples/server/petstore/aspnetcore-5.0/src/Org.OpenAPITools/Controllers/PetApi.cs
+++ b/samples/server/petstore/aspnetcore-5.0/src/Org.OpenAPITools/Controllers/PetApi.cs
@@ -81,7 +81,7 @@ namespace Org.OpenAPITools.Controllers
         /// Finds Pets by status
         /// </summary>
         /// <remarks>Multiple status values can be provided with comma separated strings</remarks>
-        /// <param name="status">Status values that need to be considered for filter</param>
+        /// <param name="status">Status values that need to be considered for filter (deprecated)</param>
         /// <response code="200">successful operation</response>
         /// <response code="400">Invalid status value</response>
         [HttpGet]
@@ -119,6 +119,7 @@ namespace Org.OpenAPITools.Controllers
         [ValidateModelState]
         [SwaggerOperation("FindPetsByTags")]
         [SwaggerResponse(statusCode: 200, type: typeof(List<Pet>), description: "successful operation")]
+        [Obsolete]
         public virtual IActionResult FindPetsByTags([FromQuery (Name = "tags")][Required()]List<string> tags)
         { 
 
diff --git a/samples/server/petstore/aspnetcore/src/Org.OpenAPITools/Controllers/PetApi.cs b/samples/server/petstore/aspnetcore/src/Org.OpenAPITools/Controllers/PetApi.cs
index 68722c6b4c..733404e0bd 100644
--- a/samples/server/petstore/aspnetcore/src/Org.OpenAPITools/Controllers/PetApi.cs
+++ b/samples/server/petstore/aspnetcore/src/Org.OpenAPITools/Controllers/PetApi.cs
@@ -108,6 +108,7 @@ namespace Org.OpenAPITools.Controllers
         [ValidateModelState]
         [SwaggerOperation("FindPetsByTags")]
         [SwaggerResponse(statusCode: 200, type: typeof(List<Pet>), description: "successful operation")]
+        [Obsolete]
         public virtual IActionResult FindPetsByTags([FromQuery (Name = "tags")][Required()]List<string> tags)
         { 
 
diff --git a/samples/server/petstore/nancyfx-async/src/Org.OpenAPITools/Modules/PetModule.cs b/samples/server/petstore/nancyfx-async/src/Org.OpenAPITools/Modules/PetModule.cs
index 28e385ce10..7ea7c76014 100644
--- a/samples/server/petstore/nancyfx-async/src/Org.OpenAPITools/Modules/PetModule.cs
+++ b/samples/server/petstore/nancyfx-async/src/Org.OpenAPITools/Modules/PetModule.cs
@@ -143,6 +143,7 @@ namespace Org.OpenAPITools._v2.Modules
         /// <param name="context">Context of request</param>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         Task<List<Pet>> FindPetsByTags(NancyContext context, List<string> tags);
 
         /// <summary>
@@ -202,6 +203,7 @@ namespace Org.OpenAPITools._v2.Modules
             return FindPetsByStatus(status);
         }
 
+        [Obsolete]
         public virtual Task<List<Pet>> FindPetsByTags(NancyContext context, List<string> tags)
         {
             return FindPetsByTags(tags);
@@ -233,6 +235,7 @@ namespace Org.OpenAPITools._v2.Modules
 
         protected abstract Task<List<Pet>> FindPetsByStatus(FindPetsByStatusStatusEnum? status);
 
+        [Obsolete]
         protected abstract Task<List<Pet>> FindPetsByTags(List<string> tags);
 
         protected abstract Task<Pet> GetPetById(long? petId);
diff --git a/samples/server/petstore/nancyfx/src/Org.OpenAPITools/Modules/PetModule.cs b/samples/server/petstore/nancyfx/src/Org.OpenAPITools/Modules/PetModule.cs
index 1223395785..8dc52f8275 100644
--- a/samples/server/petstore/nancyfx/src/Org.OpenAPITools/Modules/PetModule.cs
+++ b/samples/server/petstore/nancyfx/src/Org.OpenAPITools/Modules/PetModule.cs
@@ -142,6 +142,7 @@ namespace Org.OpenAPITools._v2.Modules
         /// <param name="context">Context of request</param>
         /// <param name="tags">Tags to filter by</param>
         /// <returns>List&lt;Pet&gt;</returns>
+        [Obsolete]
         List<Pet> FindPetsByTags(NancyContext context, List<string> tags);
 
         /// <summary>
@@ -201,6 +202,7 @@ namespace Org.OpenAPITools._v2.Modules
             return FindPetsByStatus(status);
         }
 
+        [Obsolete]
         public virtual List<Pet> FindPetsByTags(NancyContext context, List<string> tags)
         {
             return FindPetsByTags(tags);
@@ -232,6 +234,7 @@ namespace Org.OpenAPITools._v2.Modules
 
         protected abstract List<Pet> FindPetsByStatus(FindPetsByStatusStatusEnum? status);
 
+        [Obsolete]
         protected abstract List<Pet> FindPetsByTags(List<string> tags);
 
         protected abstract Pet GetPetById(long? petId);