diff --git a/src/index.ts b/src/index.ts
index 49d5534968..e4e9e04a1f 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,6 +1,7 @@
 /* Observable */
 export { Observable } from './internal/Observable';
 export { ConnectableObservable } from './internal/observable/ConnectableObservable';
+export { GroupedObservable } from './internal/operators/groupBy';
 export { Operator } from './internal/Operator';
 export { observable } from './internal/symbol/observable';
 
diff --git a/src/internal/operators/groupBy.ts b/src/internal/operators/groupBy.ts
index cf2e0fb7c5..27f965cf56 100644
--- a/src/internal/operators/groupBy.ts
+++ b/src/internal/operators/groupBy.ts
@@ -253,6 +253,7 @@ class GroupDurationSubscriber<K, T> extends Subscriber<T> {
  * @class GroupedObservable<K, T>
  */
 export class GroupedObservable<K, T> extends Observable<T> {
+  /** @deprecated Do not construct this type. Internal use only */
   constructor(public key: K,
               private groupSubject: Subject<T>,
               private refCountSubscription?: RefCountSubscription) {