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SAO PAULO, Nov 4 (Reuters) - State-run oil company Petrobras could receive as much as $20 billion from the Brazilian government in compensation for a fall in oil prices since an oil-for-stock swap in 2010, newspaper Folha de S. Paulo said on Friday.
No decision has yet been made, Petrobras said in a securities filing, adding that the amount to be paid will be determined by independent experts hired by the company and the government regulatory agency ANP.
Preferred shares of Petroleo Brasileiro SA, as the world's most indebted oil company is formally known, were up 1.7 percent. Its five-year CDS, a gauge of credit risk, fell 0.7 percent.
Petrobras received exploration rights to 5 billion barrels of oil and gas in the Santos basin in 2010 as part of a $70 billion share offering, the world's largest-ever at that time.
Terms of the sale included a renegotiation after five years, during which time Brent crude prices tumbled from above $100 a barrel to $57 at the end of 2014.
Petrobras and the government expect to conclude the renegotiation by the end of this year, Folha said, citing unidentified sources.
"This would be good news," wrote Aaron Holsberg, head of Latin American credit research at Santander. He expects the government to pay Petrobras with additional oil reserves instead of cash, given the country's record budget shortfall.
"Petrobras could partly monetize the reserves as part of its asset divestment effort," Holsberg said in a note to clients.
One government condition is that Petrobras use part of the money it receives to pay overdue taxes, Folha said.
The Finance Ministry declined to comment on the report.
Many analysts had been concerned that Petrobras would have to pay the government billions of dollars to hang on to the rights, located in Brazil's offshore subsalt region where vast deposits of oil and gas lie beneath a layer of salt.
However, Petrobras Chief Executive Pedro Parente told Reuters in late September he believed the government would end up owing Petrobras instead.. (Reporting by Bruno Federowski and Silvio Cascione; Editing by W Simon and Matthew Lewis)