Listen to the referee.

Monty Dumond of the Sharks charges ahead into big Duane Vermeulen who goes to ground while Vermeulen stays on his feet. Sharks and Stormers drive in and there is a ruck. Vermeulen's wrestles to get to the ball and as Kockott picks it up, Vermeulen knocks it from his grasp.

Off his feet and playing the ball?

Was Vermeulen off his feet?

Players are on their feet if no other part of their body is supported by the ground or players on the ground.
Sanction: Penalty kick

Vermeulen was lying on players on the ground. He was off his feet. He played the ball.

Law 16.4 (d) Players on the ground in or near the ruck must try to move away from the ball. These players must not interfere with the ball in the ruck or as it comes out of the ruck.
Sanction: Penalty kick