Jason "Poo Bear" Boyd (September 4, 1978) is an American songwriter, record producer, and vocal producer. He is best known for being one of Justin Bieber's main collaborators, having co-written many of Bieber's hits (including Where Are Ü Now, What Do You Mean?, PYD, Hold Tight and All That Matters), and for co-writing the song Caught Up from Usher's Diamond-certified album Confessions.