diff --git a/package.json b/package.json
index 45449db..82987e5 100644
--- a/package.json
+++ b/package.json
@@ -75,7 +75,7 @@
   "dependencies": {
     "@stoplight/json": "^3.18.1",
     "@stoplight/json-schema-generator": "1.0.1",
-    "@stoplight/types": "^13.5.0",
+    "@stoplight/types": "^13.6.0",
     "@types/json-schema": "7.0.11",
     "@types/swagger-schema-official": "~2.0.22",
     "@types/type-is": "^1.6.3",
diff --git a/src/oas/service.ts b/src/oas/service.ts
index 15a3ba0..d0773be 100644
--- a/src/oas/service.ts
+++ b/src/oas/service.ts
@@ -4,7 +4,7 @@ import pickBy = require('lodash.pickby');
 import { OpenAPIObject } from 'openapi3-ts';
 import { Spec } from 'swagger-schema-official';
 
-import { isNonNullable, isString } from '../guards';
+import { isBoolean, isNonNullable, isString } from '../guards';
 import { TranslateFunction } from '../types';
 import { hasXLogo } from './guards';
 import { translateTagDefinition } from './tags';
@@ -37,6 +37,13 @@ export const transformOasService: TranslateFunction<DeepPartial<OpenAPIObject> |
         },
         isPlainObject,
       ),
+
+      ...pickBy(
+        {
+          internal: document['x-internal'],
+        },
+        isBoolean,
+      ),
     };
 
     if (isPlainObject(document.info) && hasXLogo(document.info)) {
diff --git a/src/oas2/__tests__/service.test.ts b/src/oas2/__tests__/service.test.ts
index e54d7d9..8eca11c 100644
--- a/src/oas2/__tests__/service.test.ts
+++ b/src/oas2/__tests__/service.test.ts
@@ -92,6 +92,28 @@ describe('oas2 service', () => {
     const transformed = transformOas2Service({ document });
     expect(transformed).toHaveProperty(['security', 0, 'flows', 'implicit', 'scopes'], { scope_1: '' });
   });
+
+  it('should handle x-internal property', () => {
+    const document: Partial<Spec> & Fragment & { 'x-internal': boolean } = {
+      'x-stoplight': { id: 'abc' },
+      info: {
+        title: '',
+        version: '1.0',
+      },
+      'x-internal': true,
+    };
+
+    expect(
+      transformOas2Service({
+        document,
+      }),
+    ).toStrictEqual({
+      id: 'abc',
+      name: '',
+      version: '1.0',
+      internal: true,
+    });
+  });
   describe('x-logo support', () => {
     it('should support x-logo', () => {
       const document: Partial<OpenAPIObject> = {
diff --git a/src/oas3/__tests__/service.test.ts b/src/oas3/__tests__/service.test.ts
index 87961ff..96cb5c8 100644
--- a/src/oas3/__tests__/service.test.ts
+++ b/src/oas3/__tests__/service.test.ts
@@ -216,6 +216,23 @@ describe('oas3 service', () => {
     });
   });
 
+  it('should handle x-internal property', () => {
+    const document: Partial<OpenAPIObject> & { 'x-internal': boolean } = {
+      info: {
+        title: '',
+        version: '1.0',
+      },
+      'x-internal': true,
+    };
+
+    expect(transformOas3Service({ document })).toStrictEqual({
+      id: 'abc',
+      internal: true,
+      name: '',
+      version: '1.0',
+    });
+  });
+
   it('should filter out scopes', () => {
     const document: Partial<OpenAPIObject> = {
       openapi: '3.0.0',
diff --git a/yarn.lock b/yarn.lock
index a8f3c34..24119aa 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1491,10 +1491,10 @@
     "@types/json-schema" "^7.0.4"
     utility-types "^3.10.0"
 
-"@stoplight/types@^13.5.0":
-  version "13.5.0"
-  resolved "https://registry.yarnpkg.com/@stoplight/types/-/types-13.5.0.tgz#a17990ab4ff3fc60325dc64d758c4670b872ac8b"
-  integrity sha512-8UFgYj4Y/vcc3a2ZuJJ+ltiJlFsXa7/huZkmjhaHq+jPHIR2Va+aFaExENV/cWtxUVTXE15KSzPOX/ikucUFbw==
+"@stoplight/types@^13.6.0":
+  version "13.6.0"
+  resolved "https://registry.yarnpkg.com/@stoplight/types/-/types-13.6.0.tgz#96c6aaae05858b36f589821cd52c95aa9b205ce7"
+  integrity sha512-dzyuzvUjv3m1wmhPfq82lCVYGcXG0xUYgqnWfCq3PCVR4BKFhjdkHrnJ+jIDoMKvXb05AZP/ObQF6+NpDo29IQ==
   dependencies:
     "@types/json-schema" "^7.0.4"
     utility-types "^3.10.0"