diff --git a/packages/typespec-lintdiff/src/rules/consistent-patch-properties.ts b/packages/typespec-lintdiff/src/rules/consistent-patch-properties.ts
index b772cbb256..268ad341cc 100644
--- a/packages/typespec-lintdiff/src/rules/consistent-patch-properties.ts
+++ b/packages/typespec-lintdiff/src/rules/consistent-patch-properties.ts
@@ -2,6 +2,7 @@ import { resolveProviderNamespace } from "@azure-tools/typespec-azure-resource-m
 import {
   createRule,
   getDiscriminator,
+  getProperty,
   isNeverType,
   isNullType,
   paramMessage,
@@ -204,16 +205,23 @@ function getPayloadProperties(program: Program, model: Model): Map<string, Paylo
 
   for (let current: Model | undefined = model; current !== undefined; current = current.baseModel) {
     for (const property of current.properties.values()) {
+      // A derived declaration shadows its base even when its payload type is never.
+      if (getProperty(model, property.name) !== property) {
+        continue;
+      }
       const jsonName = resolveEncodedName(program, property, "application/json");
       if (!properties.has(jsonName) && !isNeverType(property.type)) {
         properties.set(jsonName, { target: property, type: property.type });
       }
     }
+  }
 
+  // Resolve the complete authored shape before filling in discriminator metadata.
+  for (let current: Model | undefined = model; current !== undefined; current = current.baseModel) {
     const discriminator = getDiscriminator(program, current);
     if (
       discriminator !== undefined &&
-      !current.properties.has(discriminator.propertyName) &&
+      getProperty(model, discriminator.propertyName) === undefined &&
       !properties.has(discriminator.propertyName)
     ) {
       properties.set(discriminator.propertyName, { target: current });
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/corpus-evidence.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/corpus-evidence.json
index 18badd6ea4..f21213e5af 100644
--- a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/corpus-evidence.json
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/corpus-evidence.json
@@ -2,16 +2,18 @@
   "schemaVersion": 2,
   "rule": "ConsistentPatchProperties",
   "specsCommit": "f6b53f105b95da05276530a0754a1c71b4f16397",
-  "generatedAt": "2026-09-09T09:24:28.545Z",
-  "completedAt": "2026-09-09T17:28:59.7719922+08:00",
-  "sourceBaseCommit": "29c4a87b0799092be0ede854ffdf23a0a9648795",
+  "generatedAt": "2026-09-11T05:20:19.336Z",
+  "completedAt": "2026-09-11T13:23:02.8497634+08:00",
+  "sourceBaseCommit": "ca14b58cdf4dfc8b1fe835c16bf3bbb30f6bdb93",
   "sourceBranch": "feature/lintdiff-consistent-patch-properties-native",
-  "sourceState": "Uncommitted native-boundary repair, before final formatting",
-  "localLinterFingerprint": "sha256:33b2527404c4fb88cc32a37f2dd7cb1d58b17789308bdce020e23635019bd6f1",
+  "sourceState": "Uncommitted inherited authored-discriminator precedence repair, after source formatting",
+  "localLinterFingerprint": "sha256:00fc4e58bfeaff393f9d36ad3bca3cd43da8cd4b00d7e46c811fb19a43e84130",
+  "diagnosticMultisetUnchangedFrom": "2026-09-11T04:09:06.638Z",
+  "diagnosticMultisetIdentity": "project + source file + line + column + message + severity, including multiplicity",
   "coverageKind": "partial",
   "command": "pnpm --dir packages/typespec-lintdiff specs:typespec --specs-repo C:\\dev\\worktrees\\azure-rest-api-specs-lintdiff-consistent-patch-properties --concurrency 6",
   "fullRun": true,
-  "durationMs": 4678050,
+  "durationMs": 1289034,
   "sourceProjectCount": 468,
   "successfulProjectCount": 462,
   "failedProjectCount": 6,
@@ -58,7 +60,7 @@
   "uncertainty": {
     "informatica": "Selected Swagger schema mismatches are verified; the validator-side omission mechanism is not isolated.",
     "versions": "The remaining 306 diagnostics are not a globally latest-version-projected population.",
-    "scope": "Four fixtures prove intentional native/emitter contract differences despite unchanged corpus counts."
+    "scope": "Four scope fixtures, two inherited-never fixtures, and two inherited-discriminator fixtures prove intentional native/emitter contract differences despite unchanged corpus findings."
   },
   "overlapProjects": [
     "specification/apimanagement/resource-manager/Microsoft.ApiManagement/ApiManagement",
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/expect.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/expect.json
new file mode 100644
index 0000000000..c8d62bd11a
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/expect.json
@@ -0,0 +1 @@
+{ "violation": false }
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/main.tsp b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/main.tsp
new file mode 100644
index 0000000000..1ef2e2e4c1
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/main.tsp
@@ -0,0 +1,41 @@
+import "../../lib/imports.tsp";
+
+using TypeSpec.Http;
+using Azure.ResourceManager;
+
+@armProviderNamespace
+@service(#{ title: "Inherited encoded PATCH discriminator" })
+namespace Microsoft.TestService;
+
+/** Authored payload inherited by the discriminated model. */
+model Base {
+  /** Object represented as kind in the JSON payload. */
+  @encodedName("application/json", "kind")
+  payload?: {
+    /** Property missing from the scalar resource kind. */
+    extra?: string;
+  };
+}
+
+/** Discriminator metadata must not replace the inherited authored object. */
+@discriminator("kind")
+model Details extends Base {}
+
+interface Operations extends Azure.ResourceManager.Operations {}
+
+/** Update the resource. */
+@route("/widgets")
+@patch
+op update(
+  /** Update body. */
+  @body body: {
+    /** Update details. */
+    details?: Details;
+  },
+): {
+  /** Resource details. */
+  details?: {
+    /** Scalar kind. */
+    kind?: string;
+  };
+};
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/output.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/output.json
new file mode 100644
index 0000000000..dbf669ea26
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/output.json
@@ -0,0 +1,160 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "Inherited encoded PATCH discriminator",
+    "version": "0000-00-00",
+    "x-typespec-generated": [
+      {
+        "emitter": "@azure-tools/typespec-autorest"
+      }
+    ]
+  },
+  "schemes": [
+    "https"
+  ],
+  "host": "management.azure.com",
+  "produces": [
+    "application/json"
+  ],
+  "consumes": [
+    "application/json"
+  ],
+  "security": [
+    {
+      "azure_auth": [
+        "user_impersonation"
+      ]
+    }
+  ],
+  "securityDefinitions": {
+    "azure_auth": {
+      "type": "oauth2",
+      "description": "Azure Active Directory OAuth2 Flow.",
+      "flow": "implicit",
+      "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
+      "scopes": {
+        "user_impersonation": "impersonate your user account"
+      }
+    }
+  },
+  "tags": [
+    {
+      "name": "Operations"
+    }
+  ],
+  "paths": {
+    "/providers/Microsoft.TestService/operations": {
+      "get": {
+        "operationId": "Operations_List",
+        "tags": [
+          "Operations"
+        ],
+        "description": "List the operations for the provider",
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v3/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/OperationListResult"
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    },
+    "/widgets": {
+      "patch": {
+        "operationId": "Update",
+        "description": "Update the resource.",
+        "parameters": [
+          {
+            "name": "body",
+            "in": "body",
+            "description": "Update body.",
+            "required": true,
+            "schema": {
+              "type": "object",
+              "properties": {
+                "details": {
+                  "$ref": "#/definitions/Details",
+                  "description": "Update details."
+                }
+              }
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "The request has succeeded.",
+            "schema": {
+              "type": "object",
+              "properties": {
+                "details": {
+                  "type": "object",
+                  "description": "Resource details.",
+                  "properties": {
+                    "kind": {
+                      "type": "string",
+                      "description": "Scalar kind."
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  },
+  "definitions": {
+    "Base": {
+      "type": "object",
+      "description": "Authored payload inherited by the discriminated model.",
+      "properties": {
+        "kind": {
+          "type": "object",
+          "description": "Object represented as kind in the JSON payload.",
+          "properties": {
+            "extra": {
+              "type": "string",
+              "description": "Property missing from the scalar resource kind."
+            }
+          },
+          "x-ms-client-name": "payload"
+        }
+      }
+    },
+    "Details": {
+      "type": "object",
+      "description": "Discriminator metadata must not replace the inherited authored object.",
+      "properties": {
+        "kind": {
+          "type": "string",
+          "description": "Discriminator property for Details."
+        }
+      },
+      "discriminator": "kind",
+      "required": [
+        "kind"
+      ],
+      "allOf": [
+        {
+          "$ref": "#/definitions/Base"
+        }
+      ]
+    }
+  },
+  "parameters": {}
+}
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/tsp-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/tsp-diagnostics.json
new file mode 100644
index 0000000000..001e35fd52
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/tsp-diagnostics.json
@@ -0,0 +1,82 @@
+[
+  {
+    "code": "@azure-tools/typespec-azure-core/require-versioned",
+    "severity": "warning",
+    "message": "Azure services should use the versioning library to define versions for their services. Add the '@versioned' decorator to the service namespace."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-common-types-version",
+    "severity": "warning",
+    "message": "Specify the ARM common-types version using the @armCommonTypesVersion decorator on the service namespace or on each version of the service version enum."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/latest-version-of-common-types-must-be-used",
+    "severity": "warning",
+    "message": "Use the latest ARM common-types version 'v6' instead of 'v3'."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/consistent-patch-properties",
+    "severity": "warning",
+    "message": "The property 'details.kind.extra' in the request body either does not appear in the resource model or is nested at the wrong level."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/composition-over-inheritance",
+    "severity": "warning",
+    "message": "Model 'Details' is extending 'Microsoft.TestService.Base' that doesn't define a discriminator. If 'Microsoft.TestService.Base' is meant to be used:\n - For composition consider using spread `...` or `model is` instead.\n - As a polymorphic relation, add the `@discriminator` decorator on the base model."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-string-discriminator",
+    "severity": "warning",
+    "message": "Use an extensible union instead of a plain string (ex: `union PetKind { cat: \"cat\", dog: \"dog\", string };`)"
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/no-empty-model",
+    "severity": "warning",
+    "message": "Properties with type:object must have definition of a reference model."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All operations must be inside an interface declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All Resource operations must use an api-version parameter. Please include Azure.ResourceManager.ApiVersionParameter in the operation parameter list using the spread (...ApiVersionParameter) operator, or using one of the common resource parameter models."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/avoid-anonymous-parameter",
+    "severity": "warning",
+    "message": "Operation request body should use a named model instead of an anonymous inline model expression."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/avoid-anonymous-types",
+    "severity": "warning",
+    "message": "Operation response body should use a named model instead of an anonymous inline model expression."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/patch-body-parameters-schema",
+    "severity": "warning",
+    "message": "Properties of a PATCH request body must not be required, property:details.kind."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/xms-examples-required",
+    "severity": "warning",
+    "message": "Please provide x-ms-examples describing minimum/maximum property set for response/request payloads for operations."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-unnamed-types",
+    "severity": "warning",
+    "message": "Anonymous model should be defined as a named model declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-unnamed-types",
+    "severity": "warning",
+    "message": "Anonymous model should be defined as a named model declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-unnamed-types",
+    "severity": "warning",
+    "message": "Anonymous model should be defined as a named model declaration."
+  }
+]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/validator-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/validator-diagnostics.json
new file mode 100644
index 0000000000..fe51488c70
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-patch/validator-diagnostics.json
@@ -0,0 +1 @@
+[]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/expect.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/expect.json
new file mode 100644
index 0000000000..ab5abad994
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/expect.json
@@ -0,0 +1,4 @@
+{
+  "violation": false,
+  "validatorDiagnostics": [{ "code": "ConsistentPatchProperties", "count": 1 }]
+}
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/main.tsp b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/main.tsp
new file mode 100644
index 0000000000..559b28317b
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/main.tsp
@@ -0,0 +1,44 @@
+import "../../lib/imports.tsp";
+
+using TypeSpec.Http;
+using Azure.ResourceManager;
+
+@armProviderNamespace
+@service(#{ title: "Inherited encoded response discriminator" })
+namespace Microsoft.TestService;
+
+/** Authored payload inherited by the discriminated model. */
+model Base {
+  /** Object represented as kind in the JSON payload. */
+  @encodedName("application/json", "kind")
+  payload?: {
+    /** Writable resource property. */
+    extra?: string;
+  };
+}
+
+/** Discriminator metadata must not replace the inherited authored object. */
+@discriminator("kind")
+model Details extends Base {}
+
+interface Operations extends Azure.ResourceManager.Operations {}
+
+/** Update the resource. */
+@route("/widgets")
+@patch
+op update(
+  /** Update body. */
+  @body body: {
+    /** Update details. */
+    details?: {
+      /** Object-valued kind. */
+      kind?: {
+        /** Updated property. */
+        extra?: string;
+      };
+    };
+  },
+): {
+  /** Resource details. */
+  details?: Details;
+};
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/output.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/output.json
new file mode 100644
index 0000000000..3bc3179475
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/output.json
@@ -0,0 +1,166 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "Inherited encoded response discriminator",
+    "version": "0000-00-00",
+    "x-typespec-generated": [
+      {
+        "emitter": "@azure-tools/typespec-autorest"
+      }
+    ]
+  },
+  "schemes": [
+    "https"
+  ],
+  "host": "management.azure.com",
+  "produces": [
+    "application/json"
+  ],
+  "consumes": [
+    "application/json"
+  ],
+  "security": [
+    {
+      "azure_auth": [
+        "user_impersonation"
+      ]
+    }
+  ],
+  "securityDefinitions": {
+    "azure_auth": {
+      "type": "oauth2",
+      "description": "Azure Active Directory OAuth2 Flow.",
+      "flow": "implicit",
+      "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
+      "scopes": {
+        "user_impersonation": "impersonate your user account"
+      }
+    }
+  },
+  "tags": [
+    {
+      "name": "Operations"
+    }
+  ],
+  "paths": {
+    "/providers/Microsoft.TestService/operations": {
+      "get": {
+        "operationId": "Operations_List",
+        "tags": [
+          "Operations"
+        ],
+        "description": "List the operations for the provider",
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v3/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/OperationListResult"
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    },
+    "/widgets": {
+      "patch": {
+        "operationId": "Update",
+        "description": "Update the resource.",
+        "parameters": [
+          {
+            "name": "body",
+            "in": "body",
+            "description": "Update body.",
+            "required": true,
+            "schema": {
+              "type": "object",
+              "properties": {
+                "details": {
+                  "type": "object",
+                  "description": "Update details.",
+                  "properties": {
+                    "kind": {
+                      "type": "object",
+                      "description": "Object-valued kind.",
+                      "properties": {
+                        "extra": {
+                          "type": "string",
+                          "description": "Updated property."
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "The request has succeeded.",
+            "schema": {
+              "type": "object",
+              "properties": {
+                "details": {
+                  "$ref": "#/definitions/Details",
+                  "description": "Resource details."
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  },
+  "definitions": {
+    "Base": {
+      "type": "object",
+      "description": "Authored payload inherited by the discriminated model.",
+      "properties": {
+        "kind": {
+          "type": "object",
+          "description": "Object represented as kind in the JSON payload.",
+          "properties": {
+            "extra": {
+              "type": "string",
+              "description": "Writable resource property."
+            }
+          },
+          "x-ms-client-name": "payload"
+        }
+      }
+    },
+    "Details": {
+      "type": "object",
+      "description": "Discriminator metadata must not replace the inherited authored object.",
+      "properties": {
+        "kind": {
+          "type": "string",
+          "description": "Discriminator property for Details."
+        }
+      },
+      "discriminator": "kind",
+      "required": [
+        "kind"
+      ],
+      "allOf": [
+        {
+          "$ref": "#/definitions/Base"
+        }
+      ]
+    }
+  },
+  "parameters": {}
+}
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/tsp-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/tsp-diagnostics.json
new file mode 100644
index 0000000000..460f947597
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/tsp-diagnostics.json
@@ -0,0 +1,77 @@
+[
+  {
+    "code": "@azure-tools/typespec-azure-core/require-versioned",
+    "severity": "warning",
+    "message": "Azure services should use the versioning library to define versions for their services. Add the '@versioned' decorator to the service namespace."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-common-types-version",
+    "severity": "warning",
+    "message": "Specify the ARM common-types version using the @armCommonTypesVersion decorator on the service namespace or on each version of the service version enum."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/latest-version-of-common-types-must-be-used",
+    "severity": "warning",
+    "message": "Use the latest ARM common-types version 'v6' instead of 'v3'."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/composition-over-inheritance",
+    "severity": "warning",
+    "message": "Model 'Details' is extending 'Microsoft.TestService.Base' that doesn't define a discriminator. If 'Microsoft.TestService.Base' is meant to be used:\n - For composition consider using spread `...` or `model is` instead.\n - As a polymorphic relation, add the `@discriminator` decorator on the base model."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-string-discriminator",
+    "severity": "warning",
+    "message": "Use an extensible union instead of a plain string (ex: `union PetKind { cat: \"cat\", dog: \"dog\", string };`)"
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/no-empty-model",
+    "severity": "warning",
+    "message": "Properties with type:object must have definition of a reference model."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All operations must be inside an interface declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All Resource operations must use an api-version parameter. Please include Azure.ResourceManager.ApiVersionParameter in the operation parameter list using the spread (...ApiVersionParameter) operator, or using one of the common resource parameter models."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/avoid-anonymous-parameter",
+    "severity": "warning",
+    "message": "Operation request body should use a named model instead of an anonymous inline model expression."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/avoid-anonymous-types",
+    "severity": "warning",
+    "message": "Operation response body should use a named model instead of an anonymous inline model expression."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/xms-examples-required",
+    "severity": "warning",
+    "message": "Please provide x-ms-examples describing minimum/maximum property set for response/request payloads for operations."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-unnamed-types",
+    "severity": "warning",
+    "message": "Anonymous model should be defined as a named model declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-unnamed-types",
+    "severity": "warning",
+    "message": "Anonymous model should be defined as a named model declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-unnamed-types",
+    "severity": "warning",
+    "message": "Anonymous model should be defined as a named model declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/no-unnamed-types",
+    "severity": "warning",
+    "message": "Anonymous model should be defined as a named model declaration."
+  }
+]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/validator-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/validator-diagnostics.json
new file mode 100644
index 0000000000..849dea5fe1
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/inherited-encoded-discriminator-response/validator-diagnostics.json
@@ -0,0 +1,15 @@
+[
+  {
+    "code": "ConsistentPatchProperties",
+    "message": "The property 'details.kind.extra' in the request body either not apppear in the resource model or has the wrong level.",
+    "path": [
+      "paths",
+      "/widgets",
+      "patch",
+      "parameters",
+      "0",
+      "schema"
+    ],
+    "severity": 0
+  }
+]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/migration.md b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/migration.md
index 6edd012244..821843b894 100644
--- a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/migration.md
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/migration.md
@@ -2,20 +2,23 @@
 
 ## Result and gap summary
 
-The September 9 full production run has **151 Swagger diagnostics in 27
+The final September 11 full production run has **151 Swagger diagnostics in 27
 projects versus 325 TypeSpec diagnostics in 32 projects**, over 462 successfully
 compiled projects; six failures are excluded from both sides. All 27 validator
-projects overlap. Counts are unchanged from September 4.
+projects overlap. Individual TypeSpec findings, including multiplicity, are
+unchanged from the earlier inheritance-repair run and September 9.
 
 The five TypeSpec-only projects contribute 19 removed/renamed-declaration
 findings and 22 Informatica findings on selected-version schema mismatches.
 The other 133 extra raw findings occur in overlapping projects, where reporting
 granularity and repeated source targets differ.
 
-**Decision: native-boundary repair completed; Swagger equivalence is partial.**
-Four scope fixtures prove three TypeSpec-only cases and one validator-only case:
-native declarations remain visible when AutoRest omits them. The unchanged
-corpus does not exercise away this contract difference.
+**Decision: both inheritance repairs completed; Swagger equivalence remains
+partial.** Native regressions correct shadowed `never` properties and inherited
+authored shapes hidden by synthetic discriminators. Four inheritance fixtures
+show opposite Swagger/native outcomes from emitted `allOf` and discriminator
+precedence. Four scope cases also differ intentionally.
+Unchanged corpus findings do not establish universal equivalence.
 
 **Limits:** Informatica's validator-side omission mechanism remains unisolated.
 Version exclusions establish the four one-sided-project exclusions, not a
@@ -23,6 +26,76 @@ globally latest-version-projected diagnostic total.
 
 ## Required changes and native contract
 
+### Inherited authored-discriminator repair
+
+Promotion of the first inheritance repair exposed another inherited-shape
+problem: synthetic discriminator metadata was inserted before the base model's
+authored properties were visited. An effective base property encoded as `kind`
+was skipped, losing its nested type. This missed PATCH mismatches and produced
+false positives when the inherited object appeared in the resource response.
+
+The helper now collects effective authored properties across the full model
+chain before filling in missing discriminator metadata. An inherited source
+property named `kind`, even when encoded differently, prevents creation of a
+second synthetic `kind`. The earlier source-name/`never` shadowing repair is
+preserved; synthetic metadata does not resurrect a shadowed authored type.
+
+Seven additional native cases cover inherited and inline request/response
+shapes, an encoded inherited discriminator source name, a genuine synthetic
+discriminator, and a `never` override combined with discriminator metadata.
+The inherited request, inherited response, and encoded-source-name cases
+exposed the old behavior. One attempted control derived from a discriminated
+base without a discriminator value was rejected by compiler
+`missing-discriminator-property`; it was replaced with a valid model carrying
+its own discriminator metadata. No suppression or special-case support was
+added for that invalid shape.
+
+The two new fixtures are valid HTTP/ARM authoring with the same object-valued
+encoded property already covered by `encoded-discriminator-property`; the
+new dimension is inheritance. In their emitted Swagger, `Base.properties.kind`
+is an object with `extra`, while `Details.properties.kind` is a synthetic string
+and `Details.allOf` references `Base`. The validator's `getProperties` merges
+the derived property over the base. Therefore it accepts the inherited PATCH
+fixture and reports `details.kind.extra` in the inherited response fixture.
+The native outcomes are the opposite: the effective authored object is used
+in both request and response comparison. These are recorded contract
+differences, not validator defects or reasons to reproduce emitter ordering.
+
+### Inherited override repair
+
+The September 11 promotion review found that skipping a derived `never`
+property allowed a later base-model walk to revive it. This caused false
+positives on PATCH bodies and missed violations on response models. The rule
+now uses compiler `getProperty(model, property.name)` to identify the effective
+declaration before resolving JSON names and filtering `never`. This also fixes
+the directly related case where an override changes its encoded name.
+
+Seven native regressions cover request/response shadowing at top-level and
+nested positions, intermediate inheritance, encoded-name overrides, a
+non-`never` redeclaration, and an unrelated property sharing an encoded name.
+Six failed before the repair; the unrelated-name control already passed.
+All snippets compile without suppressions or emitter execution.
+
+Two comparison fixtures show why native correctness does not imply Swagger
+parity. In `never-patch-override`, `Update extends Base` removes `extra` with
+`never`; the native lint correctly accepts it. Its emitted `Update.allOf`
+still references `Base`, whose `properties.extra` produces one validator
+diagnostic at `paths./widgets.patch.parameters.0.schema`.
+In `never-resource-override`, the response similarly removes `extra` natively,
+so PATCH `extra` is invalid. Emitted `Resource.allOf` still exposes the base
+property and the validator accepts it. AutoRest's `getSchemaForModel` skips
+`never` properties but preserves the base reference; the validator's
+`getProperties` merges the referenced `allOf` properties. The validator is
+checking the emitted schema correctly in both cases; it cannot observe the
+TypeSpec override. Snapshots preserve that evidence without changing the
+native contract to reproduce emission.
+
+This is an explicitly authorized source repair following merged PR #5439,
+not another initial migration. The unfinished official-library promotion
+remains separate and unchanged until this source repair is ready.
+
+### Prior native-boundary repair
+
 The repair replaces `TCGCContext` with compiler `Program`, removes
 `createTCGCContext` and all `isInScope` calls, and preserves the native PATCH
 body/response comparison. No emitter, generator context, private decorator
@@ -60,12 +133,14 @@ parameter schema and the response precedence described above. Upstream tests
 cover inherited missing properties, a matching subset, and asynchronous GET
 fallback. The scope limitations occur before this validator, during emission.
 
-| Evidence                                                           | Revision and population                                                                                                                                   | `ConsistentPatchProperties` row                                                                                                                                                                |
-| ------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| [External coverage snapshot](../../../docs/coverage_old.md)        | The checked-in snapshot links to its source gist but records no date, spec commit, or generator revision. It reports 450 compiled projects and 210 rules. | `lint`; 303 validator projects; 25 local-lint projects; 0 official projects; 8.3%. Project identities cannot be reconstructed from this aggregate row.                                         |
-| [Checked-in observed report](../../../specs/coverage-breakdown.md) | Specs commit `f6b53f105b95da05276530a0754a1c71b4f16397`; 462/468 successfully compiled projects.                                                          | Before this change: `production`; 27 validator projects; 27 TypeSpec projects; 23 overlap; 4 validator-only; 4 TypeSpec-only; 151 validator and 122 TypeSpec diagnostics.                      |
-| September 4 source evidence (historical)                           | Full review-fix run from the same specs commit; 462/468 projects compiled; duration 1,261,930 ms.                                                         | 27 validator projects; 32 TypeSpec projects; 27 overlap; 0 validator-only; 5 TypeSpec-only; 151 validator and 325 TypeSpec diagnostics.                                                        |
-| [Final retained repair evidence](./corpus-evidence.json)           | Full run generated 2026-09-09T09:24:28.545Z; completed 2026-09-09T17:28:59+08:00; same specs commit; 462/468 compiled; duration 4,678,050 ms.             | `production`; `partial` semantic coverage; 27 validator projects; 32 raw TypeSpec projects; 27 overlap; 0 validator-only; 5 raw TypeSpec-only; 151 validator and 325 raw TypeSpec diagnostics. |
+| Evidence                                                               | Revision and population                                                                                                                                   | `ConsistentPatchProperties` row                                                                                                                                                                |
+| ---------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| [External coverage snapshot](../../../docs/coverage_old.md)            | The checked-in snapshot links to its source gist but records no date, spec commit, or generator revision. It reports 450 compiled projects and 210 rules. | `lint`; 303 validator projects; 25 local-lint projects; 0 official projects; 8.3%. Project identities cannot be reconstructed from this aggregate row.                                         |
+| [Checked-in observed report](../../../specs/coverage-breakdown.md)     | Specs commit `f6b53f105b95da05276530a0754a1c71b4f16397`; 462/468 successfully compiled projects.                                                          | Before this change: `production`; 27 validator projects; 27 TypeSpec projects; 23 overlap; 4 validator-only; 4 TypeSpec-only; 151 validator and 122 TypeSpec diagnostics.                      |
+| September 4 source evidence (historical)                               | Full review-fix run from the same specs commit; 462/468 projects compiled; duration 1,261,930 ms.                                                         | 27 validator projects; 32 TypeSpec projects; 27 overlap; 0 validator-only; 5 TypeSpec-only; 151 validator and 325 TypeSpec diagnostics.                                                        |
+| September 9 native-boundary evidence (historical)                      | Full run generated 2026-09-09T09:24:28.545Z; completed 2026-09-09T17:28:59+08:00; same specs commit; 462/468 compiled; duration 4,678,050 ms.             | 27 validator projects; 32 raw TypeSpec projects; 27 overlap; 0 validator-only; 5 raw TypeSpec-only; 151 validator and 325 raw TypeSpec diagnostics.                                            |
+| September 11 inherited-override evidence (historical)                  | Full run generated 2026-09-11T04:09:06.638Z; completed 2026-09-11T12:11:44+08:00; same specs commit; 462/468 compiled; duration 1,287,834 ms.             | 27 validator projects; 32 raw TypeSpec projects; 27 overlap; 0 validator-only; 5 raw TypeSpec-only; 151 validator and 325 raw TypeSpec diagnostics.                                            |
+| [Final retained discriminator-repair evidence](./corpus-evidence.json) | Full run generated 2026-09-11T05:20:19.336Z; completed 2026-09-11T13:23:02+08:00; same specs commit; 462/468 compiled; duration 1,289,034 ms.             | `production`; `partial` semantic coverage; 27 validator projects; 32 raw TypeSpec projects; 27 overlap; 0 validator-only; 5 raw TypeSpec-only; 151 validator and 325 raw TypeSpec diagnostics. |
 
 The external report uses an unidentified older population and aggregate
 migration credit. The observed reports require same-project diagnostics on the
@@ -73,9 +148,9 @@ pinned successful-project population. The final TypeSpec diagnostic count also
 includes every declared API version; the validator dataset retains one selected
 version per project.
 
-The repair ran on `feature/lintdiff-consistent-patch-properties-native` from
-target commit `29c4a87b0799092be0ede854ffdf23a0a9648795`, with the uncommitted
-source repair included. The runner's source fingerprint is retained in
+The final discriminator repair ran on `feature/lintdiff-consistent-patch-properties-native`
+at commit `ca14b58cdf4dfc8b1fe835c16bf3bbb30f6bdb93`, with the uncommitted
+discriminator repair included. The runner's source fingerprint is retained in
 `corpus-evidence.json`. The scope is ARM, production validator execution,
 successfully compiled projects only, no readme suppressions on retained
 Swagger, and normal source-program TypeSpec diagnostics (including source
@@ -83,6 +158,15 @@ suppressions). No new global API-version projection or normalization was added.
 The checked-in coverage report is deliberately historical: refreshed canonical
 corpus artifacts are not included in this rule-repair PR.
 
+An independent comparison of the complete diagnostic multiset
+(`project`, source file, line, column, message, severity) against the retained
+September 11 inherited-override shard found no differences; that shard was
+already identical to September 9. The specs revision, successful-project
+set, one-sided project counts, and diagnostic identities are unchanged, so the
+version attribution and detailed examples below still apply to this run.
+This is observational evidence only; the new regressions expose a native shape
+gap that the corpus counts did not reveal.
+
 Six compile failures were excluded from both sides:
 
 - `specification/deviceprovisioningservices/resource-manager/Microsoft.Devices/DeviceProvisioningServices`
@@ -163,29 +247,35 @@ AutoRest's `getSchemaOrRef` selects inline or referenced schemas,
 emits nested property schemas. The Swagger rule's `diffSchema` recursively
 compares the resulting `properties` maps.
 
-| Authored shape                                                | Emitter branch / selected OpenAPI field                                                    | Swagger result | TypeSpec result | Fixture                                     |
-| ------------------------------------------------------------- | ------------------------------------------------------------------------------------------ | -------------- | --------------- | ------------------------------------------- |
-| PATCH model has a property at the wrong level                 | `getSchemaForModel` emits it in body schema `properties`; PATCH `200` response selected    | violation      | violation       | `inconsistent-patch`                        |
-| Nested PATCH-only property                                    | `resolveProperty` emits nested model `properties`                                          | violation      | violation       | `nested-extra-property`                     |
-| Custom ARM PATCH outside lifecycle registration               | operation body and response schemas use `getSchemaOrRef`                                   | violation      | violation       | `custom-patch-operation`                    |
-| PATCH has only a `201` resource response                      | response schema for `201` is selected                                                      | violation      | violation       | `patch-201-response`                        |
-| PATCH lacks `200`/`201`; same-path GET has `201`              | PATCH body emitted; GET `201` response is fallback                                         | violation      | violation       | `get-201-fallback`                          |
-| PATCH lacks `200`/`201`; same-path GET has `200`              | GET `200` response is fallback                                                             | clean          | clean           | `async-get-fallback`                        |
-| PATCH has scalar `200` and model `201` responses              | Existing `200` schema wins before its shape is interpreted                                 | violation      | violation       | `response-precedence`                       |
-| PATCH response range contains `200`                           | AutoRest emits the full `2XX` range while TypeSpec HTTP retains `{ start: 200, end: 299 }` | validator miss | violation       | focused rule unit tests                     |
-| Exact PATCH `200` overlaps a containing range                 | Explicit `200` response takes precedence over the range regardless of declaration order    | violation      | violation       | focused rule unit tests                     |
-| Different source names encode to the same JSON name           | `resolveProperty` uses the encoded property name                                           | clean          | clean           | `payload-property-shape`                    |
-| Nullable object properties have different nested properties   | nullable single-model unions emit object `properties`                                      | violation      | violation       | `nullable-object-mismatch`                  |
-| Nullable object properties have matching nested properties    | nullable single-model unions emit matching object `properties`                             | clean          | clean           | `nullable-object-match`                     |
-| Same-named array and scalar properties                        | neither property schema emits named `properties`                                           | clean          | clean           | `non-model-property-shape`                  |
-| PATCH-only property scoped to C#                              | AutoRest `isInScope` omits it from the PATCH schema                                        | clean          | violation       | `scoped-property`                           |
-| Same-path GET scoped to C#                                    | AutoRest omits the GET route, so PATCH has no fallback schema                              | clean          | violation       | `scoped-get-fallback`                       |
-| PATCH operation scoped to C#                                  | AutoRest filters the route; no PATCH operation reaches the validator                       | clean          | violation       | `scoped-patch-operation`                    |
-| Matching response property scoped to C#                       | AutoRest omits the response property but retains the PATCH property                        | violation      | clean           | `scoped-response-property`                  |
-| Undeclared PATCH discriminator                                | `getSchemaForModel` synthesizes the discriminator as a required string property            | violation      | violation       | `synthesized-discriminator`                 |
-| Authored property encodes to a synthesized discriminator name | `resolveProperty` overwrites the synthesized property with the authored property's schema  | violation      | violation       | `encoded-discriminator-property`            |
-| Same-level PATCH subset                                       | corresponding property exists in response schema                                           | clean          | clean           | `same-level-subset`                         |
-| PATCH has no body or no PATCH/GET `200`/`201` schema          | selected comparison schema is absent                                                       | clean          | clean           | guarded directly by body/response selection |
+| Authored shape                                                      | Emitter branch / selected OpenAPI field                                                                           | Swagger result | TypeSpec result                     | Fixture                                     |
+| ------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------- | -------------- | ----------------------------------- | ------------------------------------------- |
+| PATCH model has a property at the wrong level                       | `getSchemaForModel` emits it in body schema `properties`; PATCH `200` response selected                           | violation      | violation                           | `inconsistent-patch`                        |
+| Nested PATCH-only property                                          | `resolveProperty` emits nested model `properties`                                                                 | violation      | violation                           | `nested-extra-property`                     |
+| Custom ARM PATCH outside lifecycle registration                     | operation body and response schemas use `getSchemaOrRef`                                                          | violation      | violation                           | `custom-patch-operation`                    |
+| PATCH has only a `201` resource response                            | response schema for `201` is selected                                                                             | violation      | violation                           | `patch-201-response`                        |
+| PATCH lacks `200`/`201`; same-path GET has `201`                    | PATCH body emitted; GET `201` response is fallback                                                                | violation      | violation                           | `get-201-fallback`                          |
+| PATCH lacks `200`/`201`; same-path GET has `200`                    | GET `200` response is fallback                                                                                    | clean          | clean                               | `async-get-fallback`                        |
+| PATCH has scalar `200` and model `201` responses                    | Existing `200` schema wins before its shape is interpreted                                                        | violation      | violation                           | `response-precedence`                       |
+| PATCH response range contains `200`                                 | AutoRest emits the full `2XX` range while TypeSpec HTTP retains `{ start: 200, end: 299 }`                        | validator miss | violation                           | focused rule unit tests                     |
+| Exact PATCH `200` overlaps a containing range                       | Explicit `200` response takes precedence over the range regardless of declaration order                           | violation      | violation                           | focused rule unit tests                     |
+| Different source names encode to the same JSON name                 | `resolveProperty` uses the encoded property name                                                                  | clean          | clean                               | `payload-property-shape`                    |
+| Nullable object properties have different nested properties         | nullable single-model unions emit object `properties`                                                             | violation      | violation                           | `nullable-object-mismatch`                  |
+| Nullable object properties have matching nested properties          | nullable single-model unions emit matching object `properties`                                                    | clean          | clean                               | `nullable-object-match`                     |
+| Same-named array and scalar properties                              | neither property schema emits named `properties`                                                                  | clean          | clean                               | `non-model-property-shape`                  |
+| PATCH-only property scoped to C#                                    | AutoRest `isInScope` omits it from the PATCH schema                                                               | clean          | violation                           | `scoped-property`                           |
+| Same-path GET scoped to C#                                          | AutoRest omits the GET route, so PATCH has no fallback schema                                                     | clean          | violation                           | `scoped-get-fallback`                       |
+| PATCH operation scoped to C#                                        | AutoRest filters the route; no PATCH operation reaches the validator                                              | clean          | violation                           | `scoped-patch-operation`                    |
+| Matching response property scoped to C#                             | AutoRest omits the response property but retains the PATCH property                                               | violation      | clean                               | `scoped-response-property`                  |
+| Undeclared PATCH discriminator                                      | `getSchemaForModel` synthesizes the discriminator as a required string property                                   | violation      | violation                           | `synthesized-discriminator`                 |
+| Authored property encodes to a synthesized discriminator name       | `resolveProperty` overwrites the synthesized property with the authored property's schema                         | violation      | violation                           | `encoded-discriminator-property`            |
+| Valid PATCH inheritance overrides a base property with `never`      | `getSchemaForModel` omits the override but retains `allOf` and the base property                                  | violation      | clean                               | `never-patch-override`                      |
+| Valid response inheritance overrides a base property with `never`   | `getSchemaForModel` omits the override but retains `allOf` and the base property                                  | clean          | violation                           | `never-resource-override`                   |
+| Inherited PATCH object encodes to the derived discriminator name    | Derived synthetic string shadows the base object in emitted `allOf` merging; native authored object wins          | clean          | violation                           | `inherited-encoded-discriminator-patch`     |
+| Inherited response object encodes to the derived discriminator name | Derived synthetic string shadows the base object in emitted `allOf` merging; native authored object wins          | violation      | clean                               | `inherited-encoded-discriminator-response`  |
+| Inherited discriminator source name encodes differently             | Effective authored source-name lookup prevents a second native discriminator; emission is not the native contract | not asserted   | clean when the encoded name matches | native authored-discriminator tests         |
+| Valid redeclaration changes an inherited property's encoded name    | Native source-name lookup selects only the derived declaration; emission is not the native contract               | not asserted   | clean when the new name matches     | native inherited-override tests             |
+| Same-level PATCH subset                                             | corresponding property exists in response schema                                                                  | clean          | clean                               | `same-level-subset`                         |
+| PATCH has no body or no PATCH/GET `200`/`201` schema                | selected comparison schema is absent                                                                              | clean          | clean                               | guarded directly by body/response selection |
 
 Inherited properties and spreads reach the same model/property emitter
 branches. Arrays, records, scalar leaves, and empty objects have no named
@@ -562,16 +652,28 @@ one-to-one identity between operation schema paths and source properties.
 
 ## Focused validation
 
-The repair's 18 fixture snapshots were refreshed and then checked without
+The repair's 22 fixture snapshots were refreshed and then checked without
 snapshot updates. There are nine matching violation cases, five matching
-rule-compliant controls, three intentional TypeSpec-only scope cases, and one
-reviewed validator-only scope case. The harness labels the TypeSpec-only cases
+rule-compliant controls, five intentional TypeSpec-only cases, and three
+reviewed validator-only cases. The four inheritance cases add two discrepancies
+in each direction to the four existing scope cases. The harness labels the TypeSpec-only cases
 as mapped diagnostics in validator-clean fixtures; that warning is explained,
 not suppressed or reclassified as equivalence. One pre-existing non-model
 control still has unreviewed ambient diagnostics, unrelated to this rule.
 
-Nine native unit cases pass: the two existing response-range regressions,
-three emitter/client-generator-free model-comparison cases, and four client
-scope regressions. Package build and changed-file lint pass. The full corpus
+Twenty-three native unit cases pass: seven authored-discriminator cases,
+seven inherited-override regressions, the two
+existing response-range regressions, three model-comparison cases without
+AutoRest or the client generator core, and four existing client-scope
+regressions. Package build and changed-file lint pass. The full corpus
 completed with exit code zero; the six project compile failures above are
 retained and excluded, not counted as successful comparisons.
+
+The comparison runs exposed four new native/emitted inheritance
+differences; the fixture expectations now record those reviewed outcomes rather
+than claiming parity. A one-project Informatica run succeeded before the full
+run. The legacy corpus runner invokes `npm link`, so the completed runs used
+a session-local `npm_config_prefix` to isolate its link registry; the specs
+package's resolved path was checked against this source worktree. An initial
+setup-only attempt was interrupted before corpus generation and is not counted
+as a completed run. No harness implementation was changed.
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/expect.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/expect.json
new file mode 100644
index 0000000000..ab5abad994
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/expect.json
@@ -0,0 +1,4 @@
+{
+  "violation": false,
+  "validatorDiagnostics": [{ "code": "ConsistentPatchProperties", "count": 1 }]
+}
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/main.tsp b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/main.tsp
new file mode 100644
index 0000000000..5abf4d60b6
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/main.tsp
@@ -0,0 +1,38 @@
+import "../../lib/imports.tsp";
+
+using TypeSpec.Http;
+using Azure.ResourceManager;
+
+@armProviderNamespace
+@service(#{ title: "Inherited PATCH override" })
+namespace Microsoft.TestService;
+
+/** Shared update properties. */
+model Base {
+  /** Property removed by the update model. */
+  extra?: string;
+
+  /** Resource name. */
+  name?: string;
+}
+
+/** Update excludes the inherited extra property. */
+model Update extends Base {
+  extra?: never;
+}
+
+/** Resource properties. */
+model Resource {
+  /** Resource name. */
+  name?: string;
+}
+
+interface Operations extends Azure.ResourceManager.Operations {}
+
+/** Update the resource. */
+@route("/widgets")
+@patch
+op update(
+  /** Update body. */
+  @body body: Update,
+): Resource;
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/output.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/output.json
new file mode 100644
index 0000000000..ea3cbe9aec
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/output.json
@@ -0,0 +1,139 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "Inherited PATCH override",
+    "version": "0000-00-00",
+    "x-typespec-generated": [
+      {
+        "emitter": "@azure-tools/typespec-autorest"
+      }
+    ]
+  },
+  "schemes": [
+    "https"
+  ],
+  "host": "management.azure.com",
+  "produces": [
+    "application/json"
+  ],
+  "consumes": [
+    "application/json"
+  ],
+  "security": [
+    {
+      "azure_auth": [
+        "user_impersonation"
+      ]
+    }
+  ],
+  "securityDefinitions": {
+    "azure_auth": {
+      "type": "oauth2",
+      "description": "Azure Active Directory OAuth2 Flow.",
+      "flow": "implicit",
+      "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
+      "scopes": {
+        "user_impersonation": "impersonate your user account"
+      }
+    }
+  },
+  "tags": [
+    {
+      "name": "Operations"
+    }
+  ],
+  "paths": {
+    "/providers/Microsoft.TestService/operations": {
+      "get": {
+        "operationId": "Operations_List",
+        "tags": [
+          "Operations"
+        ],
+        "description": "List the operations for the provider",
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v3/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/OperationListResult"
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    },
+    "/widgets": {
+      "patch": {
+        "operationId": "Update",
+        "description": "Update the resource.",
+        "parameters": [
+          {
+            "name": "body",
+            "in": "body",
+            "description": "Update body.",
+            "required": true,
+            "schema": {
+              "$ref": "#/definitions/Update"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "The request has succeeded.",
+            "schema": {
+              "$ref": "#/definitions/Resource"
+            }
+          }
+        }
+      }
+    }
+  },
+  "definitions": {
+    "Base": {
+      "type": "object",
+      "description": "Shared update properties.",
+      "properties": {
+        "extra": {
+          "type": "string",
+          "description": "Property removed by the update model."
+        },
+        "name": {
+          "type": "string",
+          "description": "Resource name."
+        }
+      }
+    },
+    "Resource": {
+      "type": "object",
+      "description": "Resource properties.",
+      "properties": {
+        "name": {
+          "type": "string",
+          "description": "Resource name."
+        }
+      }
+    },
+    "Update": {
+      "type": "object",
+      "description": "Update excludes the inherited extra property.",
+      "allOf": [
+        {
+          "$ref": "#/definitions/Base"
+        }
+      ]
+    }
+  },
+  "parameters": {}
+}
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/tsp-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/tsp-diagnostics.json
new file mode 100644
index 0000000000..bf922bf8f9
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/tsp-diagnostics.json
@@ -0,0 +1,52 @@
+[
+  {
+    "code": "@azure-tools/typespec-azure-core/require-versioned",
+    "severity": "warning",
+    "message": "Azure services should use the versioning library to define versions for their services. Add the '@versioned' decorator to the service namespace."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-common-types-version",
+    "severity": "warning",
+    "message": "Specify the ARM common-types version using the @armCommonTypesVersion decorator on the service namespace or on each version of the service version enum."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/latest-version-of-common-types-must-be-used",
+    "severity": "warning",
+    "message": "Use the latest ARM common-types version 'v6' instead of 'v3'."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/composition-over-inheritance",
+    "severity": "warning",
+    "message": "Model 'Update' is extending 'Microsoft.TestService.Base' that doesn't define a discriminator. If 'Microsoft.TestService.Base' is meant to be used:\n - For composition consider using spread `...` or `model is` instead.\n - As a polymorphic relation, add the `@discriminator` decorator on the base model."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/documentation-required",
+    "severity": "warning",
+    "message": "The ModelProperty named 'extra' should have a documentation or description, use doc comment /** */ to provide it."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/no-override-props",
+    "severity": "warning",
+    "message": "The property 'extra' is also defined in the base model.  Redefining inherited properties can cause problems with OpenAPI tooling and some language representations of the models."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All operations must be inside an interface declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All Resource operations must use an api-version parameter. Please include Azure.ResourceManager.ApiVersionParameter in the operation parameter list using the spread (...ApiVersionParameter) operator, or using one of the common resource parameter models."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/unsupported-patch-properties",
+    "severity": "warning",
+    "message": "PATCH request body property 'name' is not patchable and should be removed or made read-only/immutable."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/xms-examples-required",
+    "severity": "warning",
+    "message": "Please provide x-ms-examples describing minimum/maximum property set for response/request payloads for operations."
+  }
+]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/validator-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/validator-diagnostics.json
new file mode 100644
index 0000000000..fd0aeb15aa
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-patch-override/validator-diagnostics.json
@@ -0,0 +1,15 @@
+[
+  {
+    "code": "ConsistentPatchProperties",
+    "message": "The property 'extra' in the request body either not apppear in the resource model or has the wrong level.",
+    "path": [
+      "paths",
+      "/widgets",
+      "patch",
+      "parameters",
+      "0",
+      "schema"
+    ],
+    "severity": 0
+  }
+]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/expect.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/expect.json
new file mode 100644
index 0000000000..c8d62bd11a
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/expect.json
@@ -0,0 +1 @@
+{ "violation": false }
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/main.tsp b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/main.tsp
new file mode 100644
index 0000000000..0ddfb8acbb
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/main.tsp
@@ -0,0 +1,38 @@
+import "../../lib/imports.tsp";
+
+using TypeSpec.Http;
+using Azure.ResourceManager;
+
+@armProviderNamespace
+@service(#{ title: "Inherited resource override" })
+namespace Microsoft.TestService;
+
+/** Shared resource properties. */
+model Base {
+  /** Property removed by the resource model. */
+  extra?: string;
+
+  /** Resource name. */
+  name?: string;
+}
+
+/** Resource excludes the inherited extra property. */
+model Resource extends Base {
+  extra?: never;
+}
+
+/** Update tries to write the excluded property. */
+model Update {
+  /** Excluded resource property. */
+  extra?: string;
+}
+
+interface Operations extends Azure.ResourceManager.Operations {}
+
+/** Update the resource. */
+@route("/widgets")
+@patch
+op update(
+  /** Update body. */
+  @body body: Update,
+): Resource;
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/output.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/output.json
new file mode 100644
index 0000000000..d0c6aabfe9
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/output.json
@@ -0,0 +1,139 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "Inherited resource override",
+    "version": "0000-00-00",
+    "x-typespec-generated": [
+      {
+        "emitter": "@azure-tools/typespec-autorest"
+      }
+    ]
+  },
+  "schemes": [
+    "https"
+  ],
+  "host": "management.azure.com",
+  "produces": [
+    "application/json"
+  ],
+  "consumes": [
+    "application/json"
+  ],
+  "security": [
+    {
+      "azure_auth": [
+        "user_impersonation"
+      ]
+    }
+  ],
+  "securityDefinitions": {
+    "azure_auth": {
+      "type": "oauth2",
+      "description": "Azure Active Directory OAuth2 Flow.",
+      "flow": "implicit",
+      "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
+      "scopes": {
+        "user_impersonation": "impersonate your user account"
+      }
+    }
+  },
+  "tags": [
+    {
+      "name": "Operations"
+    }
+  ],
+  "paths": {
+    "/providers/Microsoft.TestService/operations": {
+      "get": {
+        "operationId": "Operations_List",
+        "tags": [
+          "Operations"
+        ],
+        "description": "List the operations for the provider",
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v3/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/OperationListResult"
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v3/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    },
+    "/widgets": {
+      "patch": {
+        "operationId": "Update",
+        "description": "Update the resource.",
+        "parameters": [
+          {
+            "name": "body",
+            "in": "body",
+            "description": "Update body.",
+            "required": true,
+            "schema": {
+              "$ref": "#/definitions/Update"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "The request has succeeded.",
+            "schema": {
+              "$ref": "#/definitions/Resource"
+            }
+          }
+        }
+      }
+    }
+  },
+  "definitions": {
+    "Base": {
+      "type": "object",
+      "description": "Shared resource properties.",
+      "properties": {
+        "extra": {
+          "type": "string",
+          "description": "Property removed by the resource model."
+        },
+        "name": {
+          "type": "string",
+          "description": "Resource name."
+        }
+      }
+    },
+    "Resource": {
+      "type": "object",
+      "description": "Resource excludes the inherited extra property.",
+      "allOf": [
+        {
+          "$ref": "#/definitions/Base"
+        }
+      ]
+    },
+    "Update": {
+      "type": "object",
+      "description": "Update tries to write the excluded property.",
+      "properties": {
+        "extra": {
+          "type": "string",
+          "description": "Excluded resource property."
+        }
+      }
+    }
+  },
+  "parameters": {}
+}
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/tsp-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/tsp-diagnostics.json
new file mode 100644
index 0000000000..75f82235f9
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/tsp-diagnostics.json
@@ -0,0 +1,52 @@
+[
+  {
+    "code": "@azure-tools/typespec-azure-core/require-versioned",
+    "severity": "warning",
+    "message": "Azure services should use the versioning library to define versions for their services. Add the '@versioned' decorator to the service namespace."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-common-types-version",
+    "severity": "warning",
+    "message": "Specify the ARM common-types version using the @armCommonTypesVersion decorator on the service namespace or on each version of the service version enum."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/latest-version-of-common-types-must-be-used",
+    "severity": "warning",
+    "message": "Use the latest ARM common-types version 'v6' instead of 'v3'."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/consistent-patch-properties",
+    "severity": "warning",
+    "message": "The property 'extra' in the request body either does not appear in the resource model or is nested at the wrong level."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/composition-over-inheritance",
+    "severity": "warning",
+    "message": "Model 'Resource' is extending 'Microsoft.TestService.Base' that doesn't define a discriminator. If 'Microsoft.TestService.Base' is meant to be used:\n - For composition consider using spread `...` or `model is` instead.\n - As a polymorphic relation, add the `@discriminator` decorator on the base model."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-core/documentation-required",
+    "severity": "warning",
+    "message": "The ModelProperty named 'extra' should have a documentation or description, use doc comment /** */ to provide it."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/no-override-props",
+    "severity": "warning",
+    "message": "The property 'extra' is also defined in the base model.  Redefining inherited properties can cause problems with OpenAPI tooling and some language representations of the models."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All operations must be inside an interface declaration."
+  },
+  {
+    "code": "@azure-tools/typespec-azure-resource-manager/arm-resource-operation",
+    "severity": "warning",
+    "message": "All Resource operations must use an api-version parameter. Please include Azure.ResourceManager.ApiVersionParameter in the operation parameter list using the spread (...ApiVersionParameter) operator, or using one of the common resource parameter models."
+  },
+  {
+    "code": "tsp-lintdiff-local-linter/xms-examples-required",
+    "severity": "warning",
+    "message": "Please provide x-ms-examples describing minimum/maximum property set for response/request payloads for operations."
+  }
+]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/validator-diagnostics.json b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/validator-diagnostics.json
new file mode 100644
index 0000000000..fe51488c70
--- /dev/null
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/never-resource-override/validator-diagnostics.json
@@ -0,0 +1 @@
+[]
diff --git a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/rule.md b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/rule.md
index ecab4d044d..200ae65f3f 100644
--- a/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/rule.md
+++ b/packages/typespec-lintdiff/test/fixtures/ConsistentPatchProperties/rule.md
@@ -39,6 +39,32 @@ Swagger-compliant expectations and record a native diagnostic in their snapshots
 discrepancy. Native unit tests assert the intended result for all four cases.
 Do not add an emitter adapter or read TCGC private state to eliminate these gaps.
 
+Inherited properties are resolved by their authored name before JSON names or
+`never` filtering. A derived `extra?: never` hides `Base.extra`, including
+through intermediate models and nested payloads. A redeclaration with a new
+encoded name also replaces the base declaration rather than adding another
+property. Unrelated properties sharing a JSON name are not inheritance overrides.
+
+`never-patch-override` is native-compliant but has a reviewed validator
+diagnostic; `never-resource-override` is validator-compliant but has a native
+diagnostic. AutoRest skips the derived `never` property while emitting an
+`allOf` reference to the base, whose `extra` remains visible to the validator.
+These are native-versus-emitted contract differences, not validator defects.
+Native regression tests assert both outcomes independently of emission.
+
+Effective authored properties from the entire inheritance chain take
+precedence over synthesized discriminator metadata. The rule gathers them
+first, then adds only missing discriminators. An inherited source property
+named `kind` but encoded as `wireKind` also prevents synthesizing a second
+`kind` property. A genuine undeclared discriminator is still compared.
+
+`inherited-encoded-discriminator-patch` records a native nested mismatch that
+the validator does not report; `inherited-encoded-discriminator-response`
+records a native-compliant shape with a reviewed validator diagnostic.
+AutoRest emits a derived scalar `kind` alongside an `allOf` base containing
+the authored object-valued `kind`. The validator merges the derived property
+over the base, unlike the native effective authored-property contract.
+
 The provider namespace check isolates this ARM rule in lintdiff's mixed ruleset;
 it is not a requirement that every operation carry provider metadata. Evaluate
 that isolation separately during official ARM promotion, with ordinary and
@@ -74,26 +100,30 @@ nested-namespace coverage. This repair does not change the applicability guard.
 
 ## Test Cases
 
-| ID                               | Violation                | Description                                                                                            |
-| -------------------------------- | ------------------------ | ------------------------------------------------------------------------------------------------------ |
-| `inconsistent-patch`             | yes                      | PATCH places `displayName` at the top level even though the resource model nests it under `properties` |
-| `nested-extra-property`          | yes                      | PATCH adds `properties.extraPatchOnly`, which does not exist in the resource model                     |
-| `custom-patch-operation`         | yes                      | A custom ARM PATCH operation places `displayName` at the wrong level                                   |
-| `patch-201-response`             | yes                      | PATCH selects its `201` response model and finds a moved property                                      |
-| `get-201-fallback`               | yes                      | PATCH falls back to the same-path GET `201` response model and finds a moved property                  |
-| `response-precedence`            | yes                      | A scalar PATCH `200` response takes precedence over the matching `201` resource response               |
-| `payload-property-shape`         | no                       | Different source names encode to the same matching JSON name                                           |
-| `nullable-object-mismatch`       | yes                      | Nullable request and response objects have different nested properties                                 |
-| `nullable-object-match`          | no                       | Nullable request and response objects have the same nested properties                                  |
-| `non-model-property-shape`       | no                       | Same-named array and scalar properties both emit no nested named properties                            |
-| `scoped-property`                | no (Swagger); native yes | AutoRest omits the PATCH-only property; native lint reports it                                         |
-| `scoped-get-fallback`            | no (Swagger); native yes | AutoRest omits the GET fallback; native lint uses it                                                   |
-| `scoped-patch-operation`         | no (Swagger); native yes | AutoRest omits the PATCH endpoint; native lint checks it                                               |
-| `scoped-response-property`       | yes (Swagger); native no | AutoRest omits a matching response property; native lint accepts it                                    |
-| `synthesized-discriminator`      | yes                      | AutoRest synthesizes a PATCH discriminator property absent from the response model                     |
-| `encoded-discriminator-property` | yes                      | An encoded authored property replaces the synthesized discriminator and has a mismatching nested shape |
-| `same-level-subset`              | no                       | PATCH updates only `properties.description`, which is a valid subset of the resource model             |
-| `async-get-fallback`             | no                       | PATCH has only a `202` response, so the validator falls back to the GET resource model                 |
+| ID                                         | Violation                | Description                                                                                            |
+| ------------------------------------------ | ------------------------ | ------------------------------------------------------------------------------------------------------ |
+| `inconsistent-patch`                       | yes                      | PATCH places `displayName` at the top level even though the resource model nests it under `properties` |
+| `nested-extra-property`                    | yes                      | PATCH adds `properties.extraPatchOnly`, which does not exist in the resource model                     |
+| `custom-patch-operation`                   | yes                      | A custom ARM PATCH operation places `displayName` at the wrong level                                   |
+| `patch-201-response`                       | yes                      | PATCH selects its `201` response model and finds a moved property                                      |
+| `get-201-fallback`                         | yes                      | PATCH falls back to the same-path GET `201` response model and finds a moved property                  |
+| `response-precedence`                      | yes                      | A scalar PATCH `200` response takes precedence over the matching `201` resource response               |
+| `payload-property-shape`                   | no                       | Different source names encode to the same matching JSON name                                           |
+| `nullable-object-mismatch`                 | yes                      | Nullable request and response objects have different nested properties                                 |
+| `nullable-object-match`                    | no                       | Nullable request and response objects have the same nested properties                                  |
+| `non-model-property-shape`                 | no                       | Same-named array and scalar properties both emit no nested named properties                            |
+| `scoped-property`                          | no (Swagger); native yes | AutoRest omits the PATCH-only property; native lint reports it                                         |
+| `scoped-get-fallback`                      | no (Swagger); native yes | AutoRest omits the GET fallback; native lint uses it                                                   |
+| `scoped-patch-operation`                   | no (Swagger); native yes | AutoRest omits the PATCH endpoint; native lint checks it                                               |
+| `scoped-response-property`                 | yes (Swagger); native no | AutoRest omits a matching response property; native lint accepts it                                    |
+| `synthesized-discriminator`                | yes                      | AutoRest synthesizes a PATCH discriminator property absent from the response model                     |
+| `encoded-discriminator-property`           | yes                      | An encoded authored property replaces the synthesized discriminator and has a mismatching nested shape |
+| `same-level-subset`                        | no                       | PATCH updates only `properties.description`, which is a valid subset of the resource model             |
+| `async-get-fallback`                       | no                       | PATCH has only a `202` response, so the validator falls back to the GET resource model                 |
+| `never-patch-override`                     | yes (Swagger); native no | A native PATCH `never` override hides a base property retained by emitted `allOf`                      |
+| `never-resource-override`                  | no (Swagger); native yes | A native response `never` override hides a base property retained by emitted `allOf`                   |
+| `inherited-encoded-discriminator-patch`    | no (Swagger); native yes | An inherited authored kind object must not be replaced by synthetic scalar metadata                    |
+| `inherited-encoded-discriminator-response` | yes (Swagger); native no | An inherited authored kind object supplies the matching nested response properties                     |
 
 Focused rule unit tests additionally cover the TypeSpec HTTP representation
 where one response carries a status-code range containing `200`, including the
diff --git a/packages/typespec-lintdiff/test/rules/consistent-patch-properties.test.ts b/packages/typespec-lintdiff/test/rules/consistent-patch-properties.test.ts
index ef646a8636..e021efec74 100644
--- a/packages/typespec-lintdiff/test/rules/consistent-patch-properties.test.ts
+++ b/packages/typespec-lintdiff/test/rules/consistent-patch-properties.test.ts
@@ -30,6 +30,198 @@ beforeEach(async () => {
 });
 
 describe("consistent-patch-properties", () => {
+  describe("authored properties take precedence over synthesized discriminators", () => {
+    const service = `
+      using TypeSpec.Http;
+      @Azure.ResourceManager.armProviderNamespace
+      @service namespace Microsoft.TestService;
+    `;
+
+    for (const inherited of [false, true]) {
+      const models = inherited
+        ? `
+          model Base {
+            @encodedName("application/json", "kind") payload?: { extra?: string };
+          }
+          model Middle extends Base {}
+          @discriminator("kind") model Details extends Middle {}
+        `
+        : `
+          @discriminator("kind") model Details {
+            @encodedName("application/json", "kind") payload?: { extra?: string };
+          }
+        `;
+
+      it(`checks the nested shape of an ${inherited ? "inherited" : "inline"} encoded PATCH property`, async () => {
+        await tester
+          .expect(
+            `${service}${models}
+            @route("/widgets") @patch
+            op update(@body body: { details?: Details }): { details?: { kind?: string } };
+          `,
+          )
+          .toEmitDiagnostics({
+            code: "tsp-lintdiff-local-linter/consistent-patch-properties",
+            message:
+              "The property 'details.kind.extra' in the request body either does not appear in the resource model or is nested at the wrong level.",
+          });
+      });
+
+      it(`uses the nested shape of an ${inherited ? "inherited" : "inline"} encoded response property`, async () => {
+        await tester
+          .expect(
+            `${service}${models}
+            @route("/widgets") @patch
+            op update(@body body: { details?: { kind?: { extra?: string } } }):
+              { details?: Details };
+          `,
+          )
+          .toBeValid();
+      });
+    }
+
+    it("does not synthesize a second discriminator for an inherited authored name encoded differently", async () => {
+      await tester
+        .expect(
+          `${service}
+          model Base {
+            @encodedName("application/json", "wireKind") kind?: string;
+          }
+          @discriminator("kind") model Details extends Base {}
+          @route("/widgets") @patch
+          op update(@body body: Details): { wireKind?: string };
+        `,
+        )
+        .toBeValid();
+    });
+
+    it("still reports a synthesized discriminator with no authored property", async () => {
+      await tester
+        .expect(
+          `${service}
+          model Base { name?: string; }
+          @discriminator("kind") model Details extends Base {}
+          @route("/widgets") @patch
+          op update(@body body: Details): { name?: string };
+        `,
+        )
+        .toEmitDiagnostics({
+          code: "tsp-lintdiff-local-linter/consistent-patch-properties",
+          message:
+            "The property 'kind' in the request body either does not appear in the resource model or is nested at the wrong level.",
+        });
+    });
+
+    it("preserves a derived never override when synthesizing a discriminator", async () => {
+      await tester
+        .expect(
+          `${service}
+          model Base {
+            @encodedName("application/json", "kind") payload?: { extra?: string };
+          }
+          @discriminator("kind") model Details extends Base { payload?: never; }
+          @route("/widgets") @patch
+          op update(@body body: Details): { kind?: string };
+        `,
+        )
+        .toBeValid();
+    });
+  });
+
+  describe("inherited property overrides", () => {
+    const service = `
+      using TypeSpec.Http;
+      @Azure.ResourceManager.armProviderNamespace
+      @service namespace Microsoft.TestService;
+    `;
+
+    for (const nested of [false, true]) {
+      it(`ignores a never override in a ${nested ? "nested" : "top-level"} PATCH model`, async () => {
+        await tester
+          .expect(
+            `${service}
+            model Base { extra?: string; name?: string; }
+            model WithoutExtra extends Base { extra?: never; }
+            model Update extends WithoutExtra {}
+            model Resource { name?: string; }
+            @route("/widgets") @patch
+            op update(@body body: ${nested ? "{ properties?: Update }" : "Update"}):
+              ${nested ? "{ properties?: Resource }" : "Resource"};
+          `,
+          )
+          .toBeValid();
+      });
+
+      it(`reports a property removed by never in a ${nested ? "nested" : "top-level"} resource model`, async () => {
+        await tester
+          .expect(
+            `${service}
+            model Base { extra?: string; name?: string; }
+            model WithoutExtra extends Base { extra?: never; }
+            model Resource extends WithoutExtra {}
+            model Update { extra?: string; }
+            @route("/widgets") @patch
+            op update(@body body: ${nested ? "{ properties?: Update }" : "Update"}):
+              ${nested ? "{ properties?: Resource }" : "Resource"};
+          `,
+          )
+          .toEmitDiagnostics({
+            code: "tsp-lintdiff-local-linter/consistent-patch-properties",
+            message: `The property '${nested ? "properties.extra" : "extra"}' in the request body either does not appear in the resource model or is nested at the wrong level.`,
+          });
+      });
+    }
+
+    it("shadows an inherited property by source name before resolving its encoded name", async () => {
+      await tester
+        .expect(
+          `${service}
+          model Base { @encodedName("application/json", "oldName") extra?: string; }
+          model Update extends Base {
+            @encodedName("application/json", "newName") extra?: never;
+          }
+          @route("/widgets") @patch
+          op update(@body body: Update): { name?: string };
+        `,
+        )
+        .toBeValid();
+    });
+
+    it("does not let a never property hide a differently named inherited payload property", async () => {
+      await tester
+        .expect(
+          `${service}
+          model Base { @encodedName("application/json", "wireName") present?: string; }
+          model Update extends Base {
+            @encodedName("application/json", "wireName") removed?: never;
+          }
+          @route("/widgets") @patch
+          op update(@body body: Update): { name?: string };
+        `,
+        )
+        .toEmitDiagnostics({
+          code: "tsp-lintdiff-local-linter/consistent-patch-properties",
+          message:
+            "The property 'wireName' in the request body either does not appear in the resource model or is nested at the wrong level.",
+        });
+    });
+
+    it("uses a redeclared property's encoded name rather than its base declaration", async () => {
+      await tester
+        .expect(
+          `${service}
+          model Base { @encodedName("application/json", "oldName") value?: string; }
+          model Update extends Base {
+            @encodedName("application/json", "newName") value?: string;
+          }
+          @route("/widgets") @patch
+          op update(@body body: Update): { newName?: string };
+        `,
+        )
+        .toBeValid();
+    });
+  });
+
   it("checks nested PATCH properties without loading AutoRest or the client generator core", async () => {
     await tester
       .expect(