UPDATE 1-Brazil's Petrobras to sell up to 23.5 bln reais shares on Feb. 5 via BNDES

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BRASILIA, Jan 29 (Reuters) - Brazil’s Petrobras will price its largest share offering in a decade on Feb. 5, through which development bank BNDES will sell up to 23.5 billion reais ($5.76 billion) of shares in the oil company, it said in a securities filing.

In the filing published late on Tuesday, Petrobras said the base offering of 611,835,583 common shares at the Jan. 20 closing price of 31.98 reais could raise 19.6 billion reais, while the BNDES could sell an additional 122,367,116 shares worth 3.9 billion reais.

The last time Petrobras concluded a large share offering was in 2010, but at the time the company, rather than its shareholders, was raising money.

BNDES is in the process of returning money to the Treasury via the sale of stakes in a range of companies and paying back loans. Last year it returned some 123 billion reais, and the Economy Ministry expects it to return the full 165 billion reais of loans it still owes the government by the end of 2022.

The shares are expected to begin trading on Feb. 7 in Brazil, Petrobras said. (Reporting by Carol Mandl and Jamie McGeever, editing by Louise Heavens)