The Texas Supreme Court has rejected BP‘s claim for $750m worth of coverage under Transocean‘s insurance policies to help pay the damages related with the Gulf of Mexico oil spill in 2010.

BP has already paid more than $28bn in damages and costs associated to the oil spill, which killed 11 people and spread oil across seafood grounds and coastal beaches.

The company contracted Transocean’s Deepwater Horizon drilling rig to develop Macondo well, located in the Gulf of Mexico.

"BP is not entitled to coverage under Transocean’s insurance policies for damages arising from sub-surface pollution because BP, not Transocean, assumed liability for such claims."

The court ruled that BP is not entitled to claim status as an additional insured party under Transocean’s liability policies as the company assumed responsibility for damages associated to subsurface well pollution in the contract it signed with Transocean.

The court said: "BP is not entitled to coverage under Transocean’s insurance policies for damages arising from sub-surface pollution because BP, not Transocean, assumed liability for such claims."

In September 2014, US District Judge Carl Barbier ruled that BP’s willful misconduct and gross negligence led to the Deepwater Horizon oil spill and the company cannot recoup the additional money paid out under the old accounting method.

The British oil and gas firm paid hundreds of millions of dollars to the alleged victims of the spill through multiple businesses between August 2012 and October 2013.

The well discharged millions of barrels of oil into the Gulf of Mexico, before eventually being capped in July 2010 and permanently sealed in the following September.