Jason Boyd, better known by his stage name Poo Bear,[1] 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.