Petrojack was a Norwegian offshore drilling rig operator. The company had two jackup rigs under order from in Singapore, while it sold its two former rigs Petrojack I and Petrojack III to Maersk Drilling. The company was founded in 2004 and was listed on the Oslo Stock Exchange the next year. The largest shareholders were (40%), Awilco Offshore (18%) and Sinvest (18%).