Unlike a regular CentralBufferNode, a DataStoreNode contains objects uniquely. Source Unified Modeling Language 2.5.1
When a DataStoreNode accepts an object token, if that token contains an object with the same identity as an object contained in a token already held by the node, then the duplicate object token shall not be placed on the DataStoreNode. Source Unified Modeling Language 2.5.1
... a copy is made of the removed object token, with the same value, and this is immediately placed back onto the DataStoreNode. Thus, the values held by a DataStoreNode appear to persist for the duration of each execution of its containing activity, even Source Unified Modeling Language 2.5.1
When an offer for an object token held by a DataStoreNode is accepted by a downstream object node, the offered token is removed from the DataStoreNode, per the usual CentralBufferNode semantics. However, a copy is made of the removed object token ... Source Unified Modeling Language 2.5.1
