BP said on Monday that as part of the deal, Anadarko will no longer pursue its allegations of gross negligence against BP and that the deal excludes possible government fines the parties may have to pay.
As a 25 percent partner in the Macondo well, Anadarko was obliged to pay 25 percent of the costs of cleaning up the spill, compensating those affected and paying government fines.
It could only avoid this responsibility if it proved BP had been grossly negligent -- something which could, potentially, have added around $18bn to the total amount of fines BP faced.
BP has said the total bill for the oil spill, including government fines, for which it has taken charges of $3.5bn, will be $42bn.
This suggests Anadarko could have faced a total bill of $9.6 billion.