BJ Penn retired from mixed martial arts a December 2012 loss to Rory MacDonald, however Ariel Helwani reported on the most recent episode of UFC Tonight that Penn's retirement may not stick:
“The door is still open for BJ Penn to return to MMA in the future. He’s actually training right now and has to check in with his body and mind in the next few months. If he does come back, it will be at 155 pounds.”
Recently UFC President Dana White has stated publicly that he would like Penn to stayed retired to avoid further injuries and brain trauma, however will most likely allow Penn to return should he desire to do so.
Related MMA gear from the UG Store