diff --git a/packages/core-plugin-api/src/deprecatedTypes.ts b/packages/core-plugin-api/src/deprecatedTypes.ts
deleted file mode 100644
index 5596ff9f46..0000000000
--- a/packages/core-plugin-api/src/deprecatedTypes.ts
+++ /dev/null
@@ -1,51 +0,0 @@
-/*
- * Copyright 2020 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 {
-  Observer as CoreObserver,
-  Subscription as CoreSubscription,
-  Observable as CoreObservable,
-} from '@backstage/types';
-
-/**
- * Observer interface for consuming an Observer, see TC39.
- *
- * @public
- * @deprecated Please use the same type from `@backstage/types` instead
- */
-export type Observer<T> = CoreObserver<T>;
-
-/**
- * Subscription returned when subscribing to an Observable, see TC39.
- *
- * @public
- * @deprecated Please use the same type from `@backstage/types` instead
- */
-export type Subscription = CoreSubscription;
-
-/**
- * Observable sequence of values and errors, see TC39.
- *
- * @remarks
- *
- * {@link https://github.com/tc39/proposal-observable}
- * This is used as a common return type for observable values and can be created
- * using many different observable implementations, such as zen-observable or RxJS 5.
- *
- * @public
- * @deprecated Please use the same type from `@backstage/types` instead
- */
-export type Observable<T> = CoreObservable<T>;
diff --git a/packages/core-plugin-api/src/index.ts b/packages/core-plugin-api/src/index.ts
index 7a4f2e72ba..30fc35b62a 100644
--- a/packages/core-plugin-api/src/index.ts
+++ b/packages/core-plugin-api/src/index.ts
@@ -27,4 +27,3 @@ export * from './extensions';
 export * from './icons';
 export * from './plugin';
 export * from './routing';
-export * from './deprecatedTypes';