diff --git a/ts/smartdata.classes.collection.ts b/ts/smartdata.classes.collection.ts
index 8bd96c6..00ddd80 100644
--- a/ts/smartdata.classes.collection.ts
+++ b/ts/smartdata.classes.collection.ts
@@ -45,8 +45,9 @@ export interface IManager {
   db: SmartdataDb
 }
 
-export const setDefaultManagerForDoc = (managerArg: IManager,  dbDoc: any) => {
-  dbDoc.prototype.defaultManager = managerArg;
+export const setDefaultManagerForDoc = (managerArg: IManager,  dbDocArg: any) => {
+  dbDocArg.prototype.defaultManager = managerArg;
+  return dbDocArg;
 }
 
 /**