
One Bite At The Apple: PTAB Closes IPR Joinder Loophole
As a result of the America Invents Act enacted three years ago, the United States Patent Trial and Appeal Board (PTAB) now handles inter partes reviews (IPR)—a new trial proceeding used to challenge the validity of patent claims based on patents and printed publications. Recently, the PTAB has caused a split concerning the proper scope of the IPR joinder provision, which grants the PTAB discretion to join a “party” to a previously-instituted IPR. In the past, the PTAB interpreted the term “party” expansively to include petitioners for whom it had already instituted an IPR. Petitioners were quick to jump on this loophole, and have since sought to raise new arguments in an instituted IPR by filing a subsequent petition and seeking joinder with the in-progress proceeding.











