Shares in BP and Transocean
rose on Thursday as investors bet a new Presidential panel report that spreads the blame for the country's worst-ever oil spill means the companies will avoid a highly costly gross negligence charge.
BP's London-listed shares were up 1 percent at 504 pence at 1449 GMT, while Transocean's U.S.-listed shares were up 1.8 percent at $74.57. The STOXX 600 European oil and gas sector index was up 1 percent, on higher oil prices.
The report blamed the rig blast and subsequent spill on bad decision-making by BP, drilling contractor Transocean and well cementer Halliburton, which it said highlighted bad industry practice and regulatory shortcomings.
Haliburton shares traded down 1.4 percent at $38.86 after the report accused the company of using an unproven cement mix to seal the well, which subsequently blew out. The company denied the accusation.
Investors and analysts said the fact that the blame for the blowout was shared so widely suggested BP and Transocean were less likely to be pinned with a allegation of gross negligence.
Under U.S. law, BP faces fines of $5 billion because the spill happened on its exploration block.
However, the fines could rise above $21 billion if Europe's second-largest oil company by market value was found to have been grossly negligent in the run-up to the blast.
Peter Hitchens, oil analyst at Panmure Gordon, said comments made in the report that the management failure which caused the explosion on the Deepwater Horizon rig reflected industry-wide flaws, also made BP appear less culpable.
And while the report was damning, Richard Griffith, analyst at Evolution Securities said it could also mean BP can offload some of the costs of cleaning up the spill onto its contractors.
The report may provide grounds for BP to claw back monies from license partners and possibly Transocean and Halliburton, he said in a research note.
BP shares have gained over 60 percent since falling below 300 pence at the height of the crisis in June last year.
Halliburton and Transocean's shares have also recovered, although their performance has lagged that of rivals since November when the Presidential panel began making statements that shifted the focus of blame away from BP alone and toward its contractors.
Shares in BP's partner in the well, Anadarko Petroleum, were also hit since it stands liable for 25 percent of the spill costs but the explorer's shares have recently been buoyed by takeover speculation.
Meanwhile BP has selected a new director of communications, sources familiar with the matter said on Thursday, as it seeks to rebuild its image in the wake of the spill.
(Additional reporting by Raji Menon and Sarah Young; Editing by Greg Mahlich)