In certain embodiments, a vial adaptor for removing liquid contents from a vial comprises a piercing member and a bag. The bag can be contained within the piercing member such that the bag is introduced to the vial when the vial adaptor is coupled with the vial. In some embodiments, the bag expands within...http://www.google.de/patents/US7658733?utm_source=gb-gplus-sharePatent US7658733 - Vial for regulating pressure
