Global oil company BP PLC said Thursday its costs for fighting a massive oil spill in the Gulf of Mexico have risen by $100 million in three days to total about $450 million.
London-based BP PLC said in a filing to the U.S. Securities and Exchange Commission that the tab includes money it has given to the coastal states of Louisiana, Mississippi, Alabama and Florida and to the federal government for their responses.
The costs also include efforts to contain the crude, ongoing work to drill a relief well and settlements.
BP has estimated the price tag increases by at least $10 million a day. BP hasn't incurred any massive new expenses, and the sharp increase since Monday was likely caused by a lag in reporting costs to BP, company spokesman Mark Proegler said.
Shares of BP have fallen about 20 percent on the New York Stock Exchange since the oil rig accident.
The well has spewed more than 4 million gallons of oil into the Gulf.
Special Section: Gulf Coast Oil Disaster
Meanwhile, the company that owns the sunken Deepwater Horizon rig said Thursday it will petition a federal court in Houston to cap its overall liability from the incident at less than $27 million.
Transocean Ltd. expects to receive $560 million in insurance money from the loss of the Deepwater Horizon. If court approves the liability limit, Transocean would be left with about $533 million, almost enough to cover the company's original revenue expectations over a three-year contract with BP.
BP leases the well that's now spewing 210,000 gallons of crude into the Gulf of Mexico each day.
A spokesman for the Swiss company said the company will cite an 1851 law that says the owner of a sunken vessel is liable only for its value after the accident.
The liability limit would cap the amount that Transocean would be forced to pay if it loses any of the numerous lawsuits related to the Deepwater Horizon explosion. The company also may be able to delay other proceedings for years while a judge determines the size of Transocean's liability, said Keith Hall, a New Orleans lawyer who represents oil and gas companies.
Transocean has been named in more than 100 class-action, personal injury and wrongful death lawsuits. The plaintiffs are seeking billions of dollars in damages from a variety of interests including commercial fishermen, seafood companies, property owners and charter boat captains.
Company CEO Steven Newman told investors earlier this month that its contract with BP holds the oil giant responsible for all damages and liability from the spill.
"There is a long history of contract sanctity in our industry, and we expect that BP will honor that contract," Newman said.
But if investigators find that Transocean failed to meet federal safety guidelines, a judge could throw out any liability limits, Hall said.
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