A current implementation of this method remove: oldObject ifAbsent: exceptionBlock "Remove oldObject as one of the receiver's elements." oldObject ifNil: [ ^nil ]. ^(self protected: [ valueDictionary removeKey: oldObject ifAbsent: nil ]) ifNil: [ exceptionBlock value ] simply removes a previously registered object from registry and voila. Now lets get back to our discussion about multiple finalizers per object and using them in weak subscriptions etc. Suppose i am added a socket to weak registry, and suppose i am added a weak subscription to it. Now, if i do 'socket close' , it tells weak registry to remove it from list. And what we'll have: - socket handle is closed - socket is wiped from weak registry - but weak subscription still listed somewhere in a list of subscriptions My suggestion is, that upon #remove:, a weak registry should notify all executors that object of interest are no longer takes part in finalization scheme, so they should not count on receiving #finalize eventually. In other words: remove: oldObject ifAbsent: exceptionBlock "Remove oldObject as one of the receiver's elements." oldObject ifNil: [ ^nil ]. ^(self protected: [ | executor | executor := valueDictionary removeKey: oldObject ifAbsent: nil. executor discardFinalization. ]) ifNil: [ exceptionBlock value ] -- Best regards, Igor Stasenko AKA sig.