diff --git a/src/Microsoft.OpenApi.OData.Reader/Microsoft.OpenAPI.OData.Reader.csproj b/src/Microsoft.OpenApi.OData.Reader/Microsoft.OpenAPI.OData.Reader.csproj
index 7caef75b2..54ba66e63 100644
--- a/src/Microsoft.OpenApi.OData.Reader/Microsoft.OpenAPI.OData.Reader.csproj
+++ b/src/Microsoft.OpenApi.OData.Reader/Microsoft.OpenAPI.OData.Reader.csproj
@@ -32,7 +32,7 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
     <PackageReference Include="Microsoft.OData.Edm" Version="8.3.0" />
-    <PackageReference Include="Microsoft.OpenApi" Version="2.0.0" />
+    <PackageReference Include="Microsoft.OpenApi" Version="2.12.2" />
     <None Include="..\..\README.md" Pack="true" PackagePath="\" />
     <PackageReference Include="Microsoft.VisualStudio.Threading.Analyzers" Version="17.14.15">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/test/Microsoft.OpenAPI.OData.Reader.Tests/Generator/OpenApiSchemaGeneratorTests.cs b/test/Microsoft.OpenAPI.OData.Reader.Tests/Generator/OpenApiSchemaGeneratorTests.cs
index 8c1e550f7..162592951 100644
--- a/test/Microsoft.OpenAPI.OData.Reader.Tests/Generator/OpenApiSchemaGeneratorTests.cs
+++ b/test/Microsoft.OpenAPI.OData.Reader.Tests/Generator/OpenApiSchemaGeneratorTests.cs
@@ -391,6 +391,9 @@ public async Task CreateStructuredTypePropertiesSchemaWithCustomAttributeReturns
               ""$ref"": ""#/components/schemas/microsoft.graph.userInsightsSettings""
             },
             {
+              ""enum"": [
+                null
+              ],
               ""nullable"": true
             }
           ],
@@ -403,6 +406,9 @@ public async Task CreateStructuredTypePropertiesSchemaWithCustomAttributeReturns
               ""$ref"": ""#/components/schemas/microsoft.graph.contactMergeSuggestions""
             },
             {
+              ""enum"": [
+                null
+              ],
               ""nullable"": true
             }
           ],
@@ -415,6 +421,9 @@ public async Task CreateStructuredTypePropertiesSchemaWithCustomAttributeReturns
               ""$ref"": ""#/components/schemas/microsoft.graph.regionalAndLanguageSettings""
             },
             {
+              ""enum"": [
+                null
+              ],
               ""nullable"": true
             }
           ],
@@ -427,6 +436,9 @@ public async Task CreateStructuredTypePropertiesSchemaWithCustomAttributeReturns
               ""$ref"": ""#/components/schemas/microsoft.graph.shiftPreferences""
             },
             {
+              ""enum"": [
+                null
+              ],
               ""nullable"": true
             }
           ],
@@ -907,7 +919,8 @@ public async Task CreatePropertySchemaForNullableEnumPropertyReturnSchema(OpenAp
             string json = await schema.SerializeAsJsonAsync(specVersion);
             _output.WriteLine(json);
 
-            var expected = JsonNode.Parse(specVersion switch {
+            var expected = JsonNode.Parse(specVersion switch
+            {
                 OpenApiSpecVersion.OpenApi2_0 =>
                 """
                 {
@@ -922,6 +935,9 @@ public async Task CreatePropertySchemaForNullableEnumPropertyReturnSchema(OpenAp
                       "$ref": "#/components/schemas/DefaultNs.Color"
                     },
                     {
+                      "enum": [
+                        null
+                      ],
                       "nullable": true
                     }
                   ],
diff --git a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.json b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.json
index f2476ce60..4f9050a49 100644
--- a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.json
+++ b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.json
@@ -5016,6 +5016,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5364,6 +5367,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.Library"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5375,6 +5381,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.DocumentFile.DocumentFile"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5386,6 +5395,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5535,6 +5547,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5605,6 +5620,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5616,6 +5634,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Tags.Tag"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5864,6 +5885,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.Library"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5875,6 +5899,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.LibraryType"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -5886,6 +5913,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.Library"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -6064,6 +6094,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.LibraryType"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -6075,6 +6108,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.LibraryType"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -6590,6 +6626,9 @@
                 "$ref": "#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
diff --git a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.yaml b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.yaml
index 969f839b1..1f32eb541 100644
--- a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.yaml
+++ b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/Multiple.Schema.OpenApi.yaml
@@ -3528,7 +3528,9 @@ components:
         Document:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
       example:
         Id: 0
@@ -3805,17 +3807,23 @@ components:
         Library:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.Library'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         LastRevisionFile:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.DocumentFile.DocumentFile'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         SourceDocument:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         SourceDocumentChildren:
           type: array
@@ -3928,7 +3936,9 @@ components:
         Document:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
       example:
         ClassInstance: 0
@@ -3981,12 +3991,16 @@ components:
         Document:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         Tag:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Tags.Tag'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
       example:
         DocumentId: 0
@@ -4186,17 +4200,23 @@ components:
         LibraryParent:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.Library'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         Type:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.LibraryType'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         SourceFolder:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.Library'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         Documents:
           type: array
@@ -4333,12 +4353,16 @@ components:
         MasterLibraryType:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.LibraryType'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         ParentLibraryTypes:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Library.LibraryType'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
         MasterLibraryTypeChildren:
           type: array
@@ -4725,7 +4749,9 @@ components:
         Document:
           anyOf:
             - $ref: '#/components/schemas/Siterra.Documents.BusinessLogic.Entities.Document.Document'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           x-ms-navigationProperty: true
       example:
         Id: 0
diff --git a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.json b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.json
index 3cf1de2bd..4342cfec9 100644
--- a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.json
+++ b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.json
@@ -1418,6 +1418,9 @@
                       "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airport"
                     },
                     {
+                      "enum": [
+                        null
+                      ],
                       "nullable": true
                     }
                   ]
@@ -1452,6 +1455,9 @@
                       "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person"
                     },
                     {
+                      "enum": [
+                        null
+                      ],
                       "nullable": true
                     }
                   ]
@@ -11687,6 +11693,9 @@
                         "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person"
                       },
                       {
+                        "enum": [
+                          null
+                        ],
                         "nullable": true
                       }
                     ]
@@ -16963,6 +16972,9 @@
                         "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person"
                       },
                       {
+                        "enum": [
+                          null
+                        ],
                         "nullable": true
                       }
                     ]
@@ -30713,6 +30725,9 @@
                         "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person"
                       },
                       {
+                        "enum": [
+                          null
+                        ],
                         "nullable": true
                       }
                     ]
@@ -33731,6 +33746,9 @@
                 "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Location"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ]
@@ -33763,6 +33781,9 @@
                 "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ],
@@ -33813,6 +33834,9 @@
                 "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.AirportLocation"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ]
@@ -33833,6 +33857,9 @@
                 "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.City"
               },
               {
+                "enum": [
+                  null
+                ],
                 "nullable": true
               }
             ]
@@ -33875,6 +33902,9 @@
                     "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person"
                   },
                   {
+                    "enum": [
+                      null
+                    ],
                     "nullable": true
                   }
                 ],
@@ -34018,6 +34048,9 @@
                     "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.EventLocation"
                   },
                   {
+                    "enum": [
+                      null
+                    ],
                     "nullable": true
                   }
                 ]
@@ -34066,6 +34099,9 @@
                     "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airline"
                   },
                   {
+                    "enum": [
+                      null
+                    ],
                     "nullable": true
                   }
                 ],
@@ -34077,6 +34113,9 @@
                     "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airport"
                   },
                   {
+                    "enum": [
+                      null
+                    ],
                     "nullable": true
                   }
                 ],
@@ -34088,6 +34127,9 @@
                     "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airport"
                   },
                   {
+                    "enum": [
+                      null
+                    ],
                     "nullable": true
                   }
                 ],
@@ -34158,6 +34200,9 @@
                     "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Location"
                   },
                   {
+                    "enum": [
+                      null
+                    ],
                     "nullable": true
                   }
                 ]
@@ -34501,6 +34546,9 @@
                   "$ref": "#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airline"
                 },
                 {
+                  "enum": [
+                    null
+                  ],
                   "nullable": true
                 }
               ]
diff --git a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.yaml b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.yaml
index 330379ecf..61a79ba03 100644
--- a/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.yaml
+++ b/test/Microsoft.OpenAPI.OData.Reader.Tests/Resources/TripService.OpenApi.yaml
@@ -912,7 +912,9 @@ paths:
               schema:
                 anyOf:
                   - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airport'
-                  - nullable: true
+                  - enum:
+                      - null
+                    nullable: true
         default:
           $ref: '#/components/responses/error'
       x-ms-docs-operation-type: functionImport
@@ -932,7 +934,9 @@ paths:
               schema:
                 anyOf:
                   - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person'
-                  - nullable: true
+                  - enum:
+                      - null
+                    nullable: true
         default:
           $ref: '#/components/responses/error'
       x-ms-docs-operation-type: functionImport
@@ -7778,7 +7782,9 @@ paths:
                 hire:
                   anyOf:
                     - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person'
-                    - nullable: true
+                    - enum:
+                        - null
+                      nullable: true
       responses:
         '204':
           description: Success
@@ -11287,7 +11293,9 @@ paths:
                 hire:
                   anyOf:
                     - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person'
-                    - nullable: true
+                    - enum:
+                        - null
+                      nullable: true
       responses:
         '204':
           description: Success
@@ -20524,7 +20532,9 @@ paths:
                 hire:
                   anyOf:
                     - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person'
-                    - nullable: true
+                    - enum:
+                        - null
+                      nullable: true
       responses:
         '204':
           description: Success
@@ -22558,7 +22568,9 @@ components:
         HomeAddress:
           anyOf:
             - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Location'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
         FavoriteFeature:
           $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Feature'
         Features:
@@ -22578,7 +22590,9 @@ components:
         BestFriend:
           anyOf:
             - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
           description: The best friend.
           x-ms-navigationProperty: true
         Trips:
@@ -22611,7 +22625,9 @@ components:
         Location:
           anyOf:
             - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.AirportLocation'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
     Microsoft.OData.Service.Sample.TrippinInMemory.Models.Location:
       title: Location
       type: object
@@ -22622,7 +22638,9 @@ components:
         City:
           anyOf:
             - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.City'
-            - nullable: true
+            - enum:
+                - null
+              nullable: true
     Microsoft.OData.Service.Sample.TrippinInMemory.Models.City:
       title: City
       type: object
@@ -22647,7 +22665,9 @@ components:
             EmergencyAuthority:
               anyOf:
                 - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Person'
-                - nullable: true
+                - enum:
+                    - null
+                  nullable: true
               description: The person to contact in case of a crisis at this location.
               x-ms-navigationProperty: true
     Microsoft.OData.Service.Sample.TrippinInMemory.Models.EventLocation:
@@ -22741,7 +22761,9 @@ components:
             OccursAt:
               anyOf:
                 - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.EventLocation'
-                - nullable: true
+                - enum:
+                    - null
+                  nullable: true
             Description:
               type: string
               nullable: true
@@ -22766,17 +22788,23 @@ components:
             Airline:
               anyOf:
                 - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airline'
-                - nullable: true
+                - enum:
+                    - null
+                  nullable: true
               x-ms-navigationProperty: true
             From:
               anyOf:
                 - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airport'
-                - nullable: true
+                - enum:
+                    - null
+                  nullable: true
               x-ms-navigationProperty: true
             To:
               anyOf:
                 - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airport'
-                - nullable: true
+                - enum:
+                    - null
+                  nullable: true
               x-ms-navigationProperty: true
     Microsoft.OData.Service.Sample.TrippinInMemory.Models.Employee:
       allOf:
@@ -22812,7 +22840,9 @@ components:
             BossOffice:
               anyOf:
                 - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Location'
-                - nullable: true
+                - enum:
+                    - null
+                  nullable: true
             DirectReports:
               type: array
               items:
@@ -23029,7 +23059,9 @@ components:
           schema:
             anyOf:
               - $ref: '#/components/schemas/Microsoft.OData.Service.Sample.TrippinInMemory.Models.Airline'
-              - nullable: true
+              - enum:
+                  - null
+                nullable: true
     GetFriendsTripsResponse:
       description: Success
       content: