EXHIBIT 21.1 SUBSIDIARY COMPANIES AND STATE OR JURISDICTION OF INCORPORATION <Table> Atwood Oceanics Pacific Limited Cayman Islands, B.W.I. 100% Alpha Offshore Drilling Services Cayman Islands, B.W.I. 100% Atwood Drilling Inc. Delaware 100% Atwood Offshore Inc. Delaware 50% Atwood Hunter Co. Delaware 100% Atwood Management, Inc. Delaware 100% Atwood Deep Seas, Ltd. Texas 100% Atwood Oceanics Management, LP Delaware 100% ATW Management, Inc. Delaware 100% Eagle Oceanics, Inc. Delaware 100% Atwood Oceanics Drilling Co. Texas 100% Atwood Oceanics International, S.A. Panama 100% Atwood Oceanics Australia Pty. Ltd. Australia 100% Atwood Oceanics Platforms Pty. Ltd. Australia 100% Atwood Oceanics Services Pty. Ltd. Australia 100% Atwood Oceanics West Tuna Pty. Ltd. Australia 100% Atwood Oceanics (M) Sdn Bhd Malaysia 100% Clearways Offshore Drilling Sdn Bhd Malaysia 49% Drillquest (M) Sdn Bhd Malaysia 90% PT Alpha Offshore Drilling Indonesia 100% Aurora Offshore Services Gmbh Germany 100% </Table>