The recording industry's use of the DMCA to force ISP's to reveal the identities of file-traders make have hit a speed-bump. The US Court of Appeals for the District of Columbia has ruled that the RIAA's methods are not authorized by law. Reuters and the Associated Press are reporting that the the three-judge panel of the appeals court have overturned a trial ruling by U.S. District Judge John D. Bates. Bates previously ruled that the DMCA gave copyright holders the ability to subpoena customer names from Internet providers without filing a formal lawsuit and going through proper legal channels.

The decision to overturn that ruling seriously threatens the RIAA's legal campaign against piracy and the methodology used to obtain names from ISPs. The ruling is also certain to bring more attention to the problems with the Digital Millennium Copyright Act (DMCA), which is so broad it has been used for everything from piracy lawsuits to squabbles between printer cartridge manufacturers. It's not clear how this ruling will affect already filed subpoenas.

The full decision is available here in pdf format.