While some cat registries forbid the practice, it is now common to allow a cat to be registered by more than one registry. The World Cat Congress (WCC) is an international coordinating organization of the largest cat registries. WCC operates an "open-door" policy by which cats registered with one WCC registry can be shown under the rules of another WCC registry. Going further, the World Cat Federation, a WCC member accepts half again as many breeds as it publishes standards for, because it accepting the standards of TICA, FIFe, and several other WCC-affiliated federations, though it has also produced some nomenclatural conflicts with some of them.