American Football Rules IFAF Approved Ruling 3-3-1:III

III. Team A fumbles or the ball is loose after a backward pass. Several players dive on the ball, creating a ‘‘pile’’. RULING: The covering official(s) shall stop the clock and the 40-second clock shall start. Upon positive knowledge of who recovered, the referee will point in the direction governed by possession and start the game clock (a) immediately if Team A has recovered short of the line to gain (no first down), or (b) on the snap if Team B has recovered. [Cited by 3-3-2-e-8]