diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenModel.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenModel.java
index ccea2ee070e..438eb191294 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenModel.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenModel.java
@@ -27,7 +27,7 @@ public class CodegenModel {
     public Set<String> allMandatory;
 
     public Set<String> imports = new TreeSet<String>();
-    public Boolean hasVars, emptyVars, hasMoreModels, hasEnums, isEnum;
+    public Boolean hasVars, emptyVars, hasMoreModels, hasEnums, isEnum, hasRequired;
     public ExternalDocs externalDocs;
 
     public Map<String, Object> vendorExtensions;
diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java
index 5d71a347df0..be0f698c5b7 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java
@@ -2465,6 +2465,7 @@ public class DefaultCodegen {
     private void addVars(CodegenModel m, Map<String, Property> properties, List<String> required,
             Map<String, Property> allProperties, List<String> allRequired) {
 
+        m.hasRequired = false;
         if (properties != null && !properties.isEmpty()) {
             m.hasVars = true;
             m.hasEnums = false;
@@ -2503,6 +2504,7 @@ public class DefaultCodegen {
             } else {
                 final CodegenProperty cp = fromProperty(key, prop);
                 cp.required = mandatory.contains(key) ? true : null;
+                m.hasRequired = Boolean.TRUE.equals(m.hasRequired) || Boolean.TRUE.equals(cp.required);
                 if (cp.isEnum) {
                     // FIXME: if supporting inheritance, when called a second time for allProperties it is possible for
                     // m.hasEnums to be set incorrectly if allProperties has enumerations but properties does not.
diff --git a/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache b/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
index 2c0f8f681e3..f9b9f766299 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
@@ -20,6 +20,11 @@ namespace {{packageName}}.Client
     /// </summary>
     public class ApiClient
     {
+        private JsonSerializerSettings serializerSettings = new JsonSerializerSettings
+        {
+            ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor
+        };
+
         /// <summary>
         /// Initializes a new instance of the <see cref="ApiClient" /> class
         /// with default configuration and base path ({{basePath}}).
@@ -305,7 +310,7 @@ namespace {{packageName}}.Client
             // at this point, it must be a model (json)
             try
             {
-                return JsonConvert.DeserializeObject(response.Content, type);
+                return JsonConvert.DeserializeObject(response.Content, type, serializerSettings);
             }
             catch (Exception e)
             {
diff --git a/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache b/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache
index 4d4061a29fd..7535af0a3d8 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache
@@ -24,6 +24,13 @@
         public {{{datatypeWithEnum}}}{{#isEnum}}?{{/isEnum}} {{name}} { get; set; }
         {{/isEnum}}
         {{/vars}}
+    {{#hasRequired}}
+        /// <summary>
+        /// Initializes a new instance of the <see cref="{{classname}}" /> class.
+        /// </summary>
+        [JsonConstructorAttribute]
+        protected {{classname}}() { }
+    {{/hasRequired}}
         /// <summary>
         /// Initializes a new instance of the <see cref="{{classname}}" /> class.
         /// </summary>
diff --git a/samples/client/petstore/csharp/SwaggerClient/IO.Swagger.sln b/samples/client/petstore/csharp/SwaggerClient/IO.Swagger.sln
index 3c26ad6be49..1088cf28dc3 100644
--- a/samples/client/petstore/csharp/SwaggerClient/IO.Swagger.sln
+++ b/samples/client/petstore/csharp/SwaggerClient/IO.Swagger.sln
@@ -2,7 +2,7 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 2012
 VisualStudioVersion = 12.0.0.0
 MinimumVisualStudioVersion = 10.0.0.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "IO.Swagger", "src\IO.Swagger\IO.Swagger.csproj", "{C075FB79-0DDE-43E3-9FA5-E239EE9B9B5A}"
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "IO.Swagger", "src\IO.Swagger\IO.Swagger.csproj", "{74456AF8-75EE-4ABC-97EB-CA96A472DD21}"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "IO.Swagger.Test", "src\IO.Swagger.Test\IO.Swagger.Test.csproj", "{19F1DEBC-DE5E-4517-8062-F000CD499087}"
 EndProject
@@ -12,10 +12,10 @@ Debug|Any CPU = Debug|Any CPU
 Release|Any CPU = Release|Any CPU
 EndGlobalSection
 GlobalSection(ProjectConfigurationPlatforms) = postSolution
-{C075FB79-0DDE-43E3-9FA5-E239EE9B9B5A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-{C075FB79-0DDE-43E3-9FA5-E239EE9B9B5A}.Debug|Any CPU.Build.0 = Debug|Any CPU
-{C075FB79-0DDE-43E3-9FA5-E239EE9B9B5A}.Release|Any CPU.ActiveCfg = Release|Any CPU
-{C075FB79-0DDE-43E3-9FA5-E239EE9B9B5A}.Release|Any CPU.Build.0 = Release|Any CPU
+{74456AF8-75EE-4ABC-97EB-CA96A472DD21}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+{74456AF8-75EE-4ABC-97EB-CA96A472DD21}.Debug|Any CPU.Build.0 = Debug|Any CPU
+{74456AF8-75EE-4ABC-97EB-CA96A472DD21}.Release|Any CPU.ActiveCfg = Release|Any CPU
+{74456AF8-75EE-4ABC-97EB-CA96A472DD21}.Release|Any CPU.Build.0 = Release|Any CPU
 {19F1DEBC-DE5E-4517-8062-F000CD499087}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 {19F1DEBC-DE5E-4517-8062-F000CD499087}.Debug|Any CPU.Build.0 = Debug|Any CPU
 {19F1DEBC-DE5E-4517-8062-F000CD499087}.Release|Any CPU.ActiveCfg = Release|Any CPU
diff --git a/samples/client/petstore/csharp/SwaggerClient/README.md b/samples/client/petstore/csharp/SwaggerClient/README.md
index c546b834c18..fbeb46025d0 100644
--- a/samples/client/petstore/csharp/SwaggerClient/README.md
+++ b/samples/client/petstore/csharp/SwaggerClient/README.md
@@ -1,12 +1,12 @@
 # IO.Swagger - the C# library for the Swagger Petstore
 
-This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose.
+This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\ 
 
 This C# SDK is automatically generated by the [Swagger Codegen](https://github.com/swagger-api/swagger-codegen) project:
 
 - API version: 1.0.0
 - SDK version: 1.0.0
-- Build date: 2016-05-10T17:39:13.582+08:00
+- Build date: 2016-05-13T21:50:05.372+08:00
 - Build package: class io.swagger.codegen.languages.CSharpClientCodegen
 
 ## Frameworks supported
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger.Test/IO.Swagger.Test.csproj b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger.Test/IO.Swagger.Test.csproj
index 743b0b97853..fb3fb1ab975 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger.Test/IO.Swagger.Test.csproj
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger.Test/IO.Swagger.Test.csproj
@@ -65,7 +65,7 @@
   <Import Project="$(MsBuildToolsPath)\Microsoft.CSharp.targets" />
   <ItemGroup>
       <ProjectReference Include="..\IO.Swagger\IO.Swagger.csproj">
-          <Project>{C075FB79-0DDE-43E3-9FA5-E239EE9B9B5A}</Project>
+          <Project>{74456AF8-75EE-4ABC-97EB-CA96A472DD21}</Project>
           <Name>IO.Swagger</Name>
       </ProjectReference>
   </ItemGroup>
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Client/ApiClient.cs b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Client/ApiClient.cs
index 42299503d2a..fa4f899389a 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Client/ApiClient.cs
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Client/ApiClient.cs
@@ -18,6 +18,11 @@ namespace IO.Swagger.Client
     /// </summary>
     public class ApiClient
     {
+        private JsonSerializerSettings serializerSettings = new JsonSerializerSettings
+        {
+            ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor
+        };
+
         /// <summary>
         /// Initializes a new instance of the <see cref="ApiClient" /> class
         /// with default configuration and base path (http://petstore.swagger.io/v2).
@@ -289,7 +294,7 @@ namespace IO.Swagger.Client
             // at this point, it must be a model (json)
             try
             {
-                return JsonConvert.DeserializeObject(response.Content, type);
+                return JsonConvert.DeserializeObject(response.Content, type, serializerSettings);
             }
             catch (Exception e)
             {
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/IO.Swagger.csproj b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/IO.Swagger.csproj
index ad86456ecea..16f73d99230 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/IO.Swagger.csproj
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/IO.Swagger.csproj
@@ -3,7 +3,7 @@
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
     <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
-    <ProjectGuid>{C075FB79-0DDE-43E3-9FA5-E239EE9B9B5A}</ProjectGuid>
+    <ProjectGuid>{74456AF8-75EE-4ABC-97EB-CA96A472DD21}</ProjectGuid>
     <OutputType>Library</OutputType>
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Swagger Library</RootNamespace>
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Animal.cs b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Animal.cs
index 87a17aa4fae..ba5bf4d2ab4 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Animal.cs
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Animal.cs
@@ -17,6 +17,11 @@ namespace IO.Swagger.Model
     [DataContract]
     public partial class Animal :  IEquatable<Animal>
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Animal" /> class.
+        /// </summary>
+        [JsonConstructorAttribute]
+        protected Animal() { }
         /// <summary>
         /// Initializes a new instance of the <see cref="Animal" /> class.
         /// </summary>
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Cat.cs b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Cat.cs
index fee880c5d82..10ea622f999 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Cat.cs
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Cat.cs
@@ -17,6 +17,11 @@ namespace IO.Swagger.Model
     [DataContract]
     public partial class Cat : Animal,  IEquatable<Cat>
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Cat" /> class.
+        /// </summary>
+        [JsonConstructorAttribute]
+        protected Cat() { }
         /// <summary>
         /// Initializes a new instance of the <see cref="Cat" /> class.
         /// </summary>
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Dog.cs b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Dog.cs
index fb65e3e0c99..bbd61a8535b 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Dog.cs
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Dog.cs
@@ -17,6 +17,11 @@ namespace IO.Swagger.Model
     [DataContract]
     public partial class Dog : Animal,  IEquatable<Dog>
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Dog" /> class.
+        /// </summary>
+        [JsonConstructorAttribute]
+        protected Dog() { }
         /// <summary>
         /// Initializes a new instance of the <see cref="Dog" /> class.
         /// </summary>
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/FormatTest.cs b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/FormatTest.cs
index 33301f02a95..51c2d920e30 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/FormatTest.cs
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/FormatTest.cs
@@ -17,6 +17,11 @@ namespace IO.Swagger.Model
     [DataContract]
     public partial class FormatTest :  IEquatable<FormatTest>
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FormatTest" /> class.
+        /// </summary>
+        [JsonConstructorAttribute]
+        protected FormatTest() { }
         /// <summary>
         /// Initializes a new instance of the <see cref="FormatTest" /> class.
         /// </summary>
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Name.cs b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Name.cs
index 25273ffb97b..6ca08ca5f7e 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Name.cs
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Name.cs
@@ -17,6 +17,11 @@ namespace IO.Swagger.Model
     [DataContract]
     public partial class Name :  IEquatable<Name>
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Name" /> class.
+        /// </summary>
+        [JsonConstructorAttribute]
+        protected Name() { }
         /// <summary>
         /// Initializes a new instance of the <see cref="Name" /> class.
         /// </summary>
diff --git a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Pet.cs b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Pet.cs
index 420ab138b07..50cdb903f94 100644
--- a/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Pet.cs
+++ b/samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Model/Pet.cs
@@ -53,6 +53,11 @@ namespace IO.Swagger.Model
         /// <summary>
         /// Initializes a new instance of the <see cref="Pet" /> class.
         /// </summary>
+        [JsonConstructorAttribute]
+        protected Pet() { }
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Pet" /> class.
+        /// </summary>
         /// <param name="Id">Id.</param>
         /// <param name="Category">Category.</param>
         /// <param name="Name">Name (required).</param>
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs b/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs
index b87503528b6..a232c3d0177 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs
+++ b/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs
@@ -5,7 +5,7 @@
       <File FileName="TestPet.cs" Line="1" Column="1" />
       <File FileName="TestOrder.cs" Line="1" Column="1" />
       <File FileName="../SwaggerClient/src/IO.Swagger/Api/FakeApi.cs" Line="1" Column="1" />
-      <File FileName="../SwaggerClient/src/IO.Swagger/Model/ApiResponse.cs" Line="1" Column="1" />
+      <File FileName="../SwaggerClient/src/IO.Swagger/Model/ApiResponse.cs" Line="13" Column="2" />
     </Files>
   </MonoDevelop.Ide.Workbench>
   <MonoDevelop.Ide.DebuggingService.Breakpoints>