Just two offshore companies accounted for 45 percent of the total owed creditors this year, the law firm's figures show. Deepwater offshore services firm Seadrill Ltd's (OL: SDRL ) September filing was the largest bankruptcy this year with $8 billion in debts, while Ocean Rig UDW Inc (O: ORIG ) filed owing $3.6 billion. On Nov. 12, another offshore driller, Pacific Drilling [PDSAX.UL], filed for bankruptcy protection with $3.2 billion owed to creditors. That filing was not included in the survey. Oil prices have rebounded this year with the U.S. benchmark ( CLc1 ) up 22 percent in the last 52 weeks to about $55 a barrel. That gain has stirred onshore drilling and production but has not been enough to boost the more costly offshore and deepwater drilling. "If you're going to get $50 a barrel oil you want the cheapest way of getting that barrel and offshore isn't it," Ian Peck, chairman of Haynes and Boone's restructuring practice group, said in an interview.