diff --git a/packages/frontend-app-api/src/wiring/createSpecializedApp.test.tsx b/packages/frontend-app-api/src/wiring/createSpecializedApp.test.tsx
index 8a4e2b5c9b..5a011c058e 100644
--- a/packages/frontend-app-api/src/wiring/createSpecializedApp.test.tsx
+++ b/packages/frontend-app-api/src/wiring/createSpecializedApp.test.tsx
@@ -423,7 +423,7 @@ describe('createSpecializedApp', () => {
     expect(app.apis.get(testApiRef)).toEqual({ value: 'owner' });
   });
 
-  it('should ignore plugin ownership metadata from unsupported opaque ApiRefs', () => {
+  it('should reject unsupported opaque ApiRef versions', () => {
     const testApiRef = {
       $$type: '@backstage/ApiRef',
       version: 'v0',
@@ -439,46 +439,39 @@ describe('createSpecializedApp', () => {
       readonly pluginId: 'owner';
     };
 
-    const app = createSpecializedApp({
-      features: [
-        makeAppPlugin(),
-        createFrontendPlugin({
-          pluginId: 'other-before',
-          extensions: [
-            ApiBlueprint.make({
-              params: defineParams =>
-                defineParams({
-                  api: testApiRef,
-                  deps: {},
-                  factory: () => ({ value: 'other' }),
-                }),
-            }),
-          ],
-        }),
-        createFrontendPlugin({
-          pluginId: 'owner',
-          extensions: [
-            ApiBlueprint.make({
-              params: defineParams =>
-                defineParams({
-                  api: testApiRef,
-                  deps: {},
-                  factory: () => ({ value: 'owner' }),
-                }),
-            }),
-          ],
-        }),
-      ],
-    });
-
-    expect(app.errors).toEqual([
-      expect.objectContaining({
-        code: 'API_FACTORY_CONFLICT',
-        message: expect.stringContaining("API 'shared.api'"),
+    expect(() =>
+      createSpecializedApp({
+        features: [
+          makeAppPlugin(),
+          createFrontendPlugin({
+            pluginId: 'other-before',
+            extensions: [
+              ApiBlueprint.make({
+                params: defineParams =>
+                  defineParams({
+                    api: testApiRef,
+                    deps: {},
+                    factory: () => ({ value: 'other' }),
+                  }),
+              }),
+            ],
+          }),
+          createFrontendPlugin({
+            pluginId: 'owner',
+            extensions: [
+              ApiBlueprint.make({
+                params: defineParams =>
+                  defineParams({
+                    api: testApiRef,
+                    deps: {},
+                    factory: () => ({ value: 'owner' }),
+                  }),
+              }),
+            ],
+          }),
+        ],
       }),
-    ]);
-
-    expect(app.apis.get(testApiRef)).toEqual({ value: 'other' });
+    ).toThrow("Invalid opaque type instance, got version 'v0', expected 'v1'");
   });
 
   it('should not infer app ownership from core-prefixed API ids', () => {
diff --git a/packages/frontend-app-api/src/wiring/createSpecializedApp.tsx b/packages/frontend-app-api/src/wiring/createSpecializedApp.tsx
index 20c00c8929..0c47dca6f6 100644
--- a/packages/frontend-app-api/src/wiring/createSpecializedApp.tsx
+++ b/packages/frontend-app-api/src/wiring/createSpecializedApp.tsx
@@ -43,6 +43,7 @@ import {
 import { ApiFactoryRegistry, ApiResolver } from '@backstage/core-app-api';
 import {
   createExtensionDataContainer,
+  OpaqueApiRef,
   OpaqueFrontendPlugin,
 } from '@internal/frontend';
 
@@ -51,8 +52,6 @@ import {
   resolveExtensionDefinition,
   toInternalExtension,
 } from '../../../frontend-plugin-api/src/wiring/resolveExtensionDefinition';
-// eslint-disable-next-line @backstage/no-relative-monorepo-imports
-import { OpaqueApiRef } from '../../../frontend-plugin-api/src/apis/system/ApiRef';
 
 import {
   extractRouteInfoFromAppNode,
@@ -459,13 +458,9 @@ function createApiFactories(options: {
 //               might need to wait for some future update for API factories.
 function getApiOwnerId(apiRef: { id: string }): string {
   if (OpaqueApiRef.isType(apiRef)) {
-    try {
-      const { pluginId } = OpaqueApiRef.toInternal(apiRef);
-      if (pluginId) {
-        return pluginId;
-      }
-    } catch {
-      // Fall back to legacy ID inference for unsupported opaque ApiRef versions.
+    const { pluginId } = OpaqueApiRef.toInternal(apiRef);
+    if (pluginId) {
+      return pluginId;
     }
   }
 
diff --git a/packages/frontend-internal/src/apis/OpaqueApiRef.ts b/packages/frontend-internal/src/apis/OpaqueApiRef.ts
new file mode 100644
index 0000000000..8a1b058641
--- /dev/null
+++ b/packages/frontend-internal/src/apis/OpaqueApiRef.ts
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2024 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import type { ApiRef } from '@backstage/frontend-plugin-api';
+import { OpaqueType } from '@internal/opaque';
+
+export const OpaqueApiRef = OpaqueType.create<{
+  public: ApiRef<unknown> & {
+    readonly $$type: '@backstage/ApiRef';
+  };
+  versions: {
+    readonly version: 'v1';
+    readonly pluginId?: string;
+  };
+}>({
+  type: '@backstage/ApiRef',
+  versions: ['v1'],
+});
diff --git a/packages/frontend-internal/src/apis/index.ts b/packages/frontend-internal/src/apis/index.ts
new file mode 100644
index 0000000000..f445683652
--- /dev/null
+++ b/packages/frontend-internal/src/apis/index.ts
@@ -0,0 +1,17 @@
+/*
+ * Copyright 2024 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+export * from './OpaqueApiRef';
diff --git a/packages/frontend-internal/src/index.ts b/packages/frontend-internal/src/index.ts
index 38bfdc53f8..447b488fca 100644
--- a/packages/frontend-internal/src/index.ts
+++ b/packages/frontend-internal/src/index.ts
@@ -15,4 +15,5 @@
  */
 
 export * from './routing';
+export * from './apis';
 export * from './wiring';
diff --git a/packages/frontend-plugin-api/src/apis/system/ApiRef.ts b/packages/frontend-plugin-api/src/apis/system/ApiRef.ts
index 2327cb0631..557341d98a 100644
--- a/packages/frontend-plugin-api/src/apis/system/ApiRef.ts
+++ b/packages/frontend-plugin-api/src/apis/system/ApiRef.ts
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { OpaqueType } from '@internal/opaque';
+import { OpaqueApiRef } from '@internal/frontend';
 import type { ApiRef } from './types';
 
 /**
@@ -31,20 +31,6 @@ type ApiRefBuilderConfig<TId extends string> = {
   pluginId?: string;
 };
 
-/** @internal */
-export const OpaqueApiRef = OpaqueType.create<{
-  public: ApiRef<unknown> & {
-    readonly $$type: '@backstage/ApiRef';
-  };
-  versions: {
-    readonly version: 'v1';
-    readonly pluginId?: string;
-  };
-}>({
-  type: '@backstage/ApiRef',
-  versions: ['v1'],
-});
-
 function validateId(id: string): void {
   const valid = id
     .split('.')