Although entities should have an independent existence within an application domain, there can be a weak emtity instance whose existence is dependent on another entity instance (technically called the identifying owner).
Ingawa vyombo wanapaswa kuwa na kuwepo huru ndani ya maombi ya uwanja, kuna kuwa dhaifu emtity mfano ambao kuwepo ni tegemezi kwa mfano mwingine chombo (kitaalam inaitwa mmiliki kutambua).