Operation of its rigs was done by the company Premium Drilling, owned by Awilco and Sinvest.

The company was founded in February 2005 when it took over the offshore rig assets of Anders Wilhelmsen Group and at the same time acquiring NOK 1 billion in new capital.

The company accepted a $2.5 billion acquisition offer from industry peer China Oilfield Services on 7 July 2008.

[1] The deal was approved by the China Securities Regulatory Commission in September[2] and a compulsory acquisition of outstanding shares was completed that November.

[3] Awilco Offshore was fully integrated into the firm's local subsidiary COSL Norwegian AS.