Board Thread:Questions and Answers/@comment-5239435-20130206201307/@comment-8986886-20130501144702

From what I understand, when a shinigami dies, his/her spirit will leave the Zanpakuto. Without that spirit the Asauchi will be 'reset' to its original state, as if it had never had a master.

So the next shinigami to master that Asauchi, would give birth to a new Zanpakuto with different powers from the previous one(s).