diff --git a/src/index.ts b/src/index.ts
index 614ce0d1..ae530efe 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -30,7 +30,9 @@ async function validate(input: ValidateSchemaInput<unknown, unknown>): Promise<S
 }
 
 async function parse(input: ParseSchemaInput<unknown, unknown>): Promise<SpecTypesV2.SchemaObject> {
-  const transformed = toJsonSchema(input.data, {
+  // cloning input, because input schema is modified during transformation despite setting cloneSchema
+  const inputSchema = structuredClone(input.data);
+  const transformed = toJsonSchema(inputSchema, {
     cloneSchema: true,
     keepNotSupported: [
       'discriminator',
@@ -119,4 +121,4 @@ function getAjvInstance(): Ajv {
   ajv.addSchema(jsonSchemaV3, 'openapi');
 
   return ajv;
-}
\ No newline at end of file
+}
diff --git a/test/documents/asyncapi3.yaml b/test/documents/asyncapi3.yaml
new file mode 100644
index 00000000..d846b95b
--- /dev/null
+++ b/test/documents/asyncapi3.yaml
@@ -0,0 +1,62 @@
+asyncapi: 3.0.0
+info:
+  title: Address change events
+  version: 1.0.0
+defaultContentType: application/json
+channels:
+  AddressEventsChannel:
+    messages:
+      addressAdded:
+        $ref: '#/components/messages/AddressAddedEvent'
+      addressUpdated:
+        $ref: '#/components/messages/AddressUpdatedEvent'
+operations:
+  receiveAddressNotification:
+    action: receive
+    channel:
+      $ref: '#/channels/AddressEventsChannel'
+components:
+  messages:
+    AddressAddedEvent:
+      payload:
+        schemaFormat: application/vnd.oai.openapi+yaml;version=3.0.0
+        schema:
+          $ref: '#/components/schemas/AddressAddedEvent'
+    AddressUpdatedEvent:
+      payload:
+        schemaFormat: application/vnd.oai.openapi+yaml;version=3.0.0
+        schema:
+          $ref: '#/components/schemas/AddressUpdatedEvent'
+  schemas:
+    EventBase:
+      type: object
+      properties:
+        time2:
+          type: string
+          nullable: true       
+    AddressEvent:
+      allOf:
+      - $ref: "#/components/schemas/EventBase"
+      type: object
+      properties:
+        type:
+          type: string
+        time:
+          type: string
+          nullable: true      
+      required:
+        - type
+    AddressAddedEvent:
+      type: object
+      allOf:
+        - $ref: "#/components/schemas/AddressEvent"
+      properties:
+        addedAddress:
+          type: string
+    AddressUpdatedEvent:
+      allOf:
+        - $ref: "#/components/schemas/AddressEvent"
+      type: object
+      properties:
+        updatedAddress:
+          type: string
diff --git a/test/parser.spec.ts b/test/parser.spec.ts
index 2cdd7687..a904fd2d 100644
--- a/test/parser.spec.ts
+++ b/test/parser.spec.ts
@@ -12,6 +12,8 @@ const inputWithInvalidOpenApi3 = toParseInput(fs.readFileSync(path.resolve(__dir
 
 const inputWithValidAsyncAPI = fs.readFileSync(path.resolve(__dirname, './documents/valid-asyncapi.yaml'), 'utf8');
 
+const inputWithValidAsyncAPI3 = fs.readFileSync(path.resolve(__dirname, './documents/asyncapi3.yaml'), 'utf8');
+
 const inputWithInvalidAsyncAPI = fs.readFileSync(path.resolve(__dirname, './documents/invalid-asyncapi.yaml'), 'utf8');
 
 describe('OpenAPISchemaParser', function () {
@@ -70,6 +72,11 @@ describe('OpenAPISchemaParser', function () {
     doParseCoreTest((document?.json()?.components?.messages?.testMessage as any)?.payload, outputWithValidOpenApi3);
   });
 
+  it('should parse valid AsyncAPI3', async function() {
+    const { document, diagnostics } = await coreParser.parse(inputWithValidAsyncAPI3);
+    expect(diagnostics).toHaveLength(0);
+  });
+
   it('should validate valid AsyncAPI', async function() {
     const diagnostics = await coreParser.validate(inputWithValidAsyncAPI);
     expect(filterDiagnostics(diagnostics, 'asyncapi2-schemas')).toHaveLength(0);
@@ -181,4 +188,4 @@ function filterDiagnostics(diagnostics: Diagnostic[], code: string) {
 
 function expectDiagnostics(diagnostics: Diagnostic[], code: string, results: SchemaValidateResult[]) {
   expect(filterDiagnostics(diagnostics, code)).toEqual(results.map(e => expect.objectContaining(e)));
-}
\ No newline at end of file
+}