Rainer Oppermann deals with the collision of claims. The starting point is the collision between vindication and obligations arising from the transfer of possession. The author also addresses general questions regarding claim collisions. A claim collision occurs when a debtor is obligated to two different creditors but can only fulfill his debt obligation once due to the nature of the claims. This proves to be problematic, as the claims of different creditors mutually influence each other, even though they actually stand alongside each other without any internal connection. This necessitates the determination of a ranking relationship between the claims. However, there is no statutory regulation regarding the ranking relationship, and the question of the ranking relationship remains unresolved in both case law and literature.