1. Aban Offshore Limited
2. CARE Industries Ltd.
3. China Oilfield Services Limited
4. Diamond Offshore Drilling Inc.
5. Ensign Energy Services Inc.
6. Eurasia Drilling Company Limited
7. Halliburton Energy Services Inc.
8. Helmerich & Payne Inc.
9. KCA Deutag
10. Nabors Industries Limited
11. Noble Corporation PLC
12. Pacific Drilling Co.
13. Patterson-UTI Energy Inc.
14. Precision Drilling Corporation
15. Saipem S.p.A.