Fox has served YouTube with a subpoena in an effort to discover the identity of the person who recently uploaded entire episodes of The Simpsons and 24. 

The subpoena was granted by the U.S. District Court for the Northern District of California on Jan. 18 and served this Wednesday, writes the Hollywood Reporter (via Reuters). Whether YouTube has complied is not yet known. Another video-sharing site, LiveDigital, was served a similar subpoena.

The uploaded episodes of 24, which were the basis of the subpoena, actually appeared on YouTube prior to the Jan. 14 season premiere on the Fox broadcast network. Fox was made aware of the uploaded episodes on Jan. 8, according to the subpoena.

Filed with the Digital Millennium Copyright Act as its basis, the subpoena includes testimony from Fox Entertainment Group VP Jane Sunderland, who suggests that Fox had been unable to determine the video uploader’s identity on its own.