Shares of Brazilian state-run energy company Petroleo Brasileiro (PBR, PETR4.BR), or Petrobras, jumped in early trade Thursday ahead of the pricing of the company's massive share offer.

Petrobras shares climbed 2.9% to 26.75 Brazilian reals ($15.52) in early trade on the Sao Paulo Stock Exchange, then advanced to BRL27.13, or 4.3%, at 1430 GMT.

The strong move could indicate that the price for the world's largest share offer could come in at the top of the BRL25.00 to BRL26.00 range expected by the market, a fund manager told Dow Jones Newswires.

"We expect the pricing to come in at BRL25.50, but this movement is strange," the fund manager said. "That could indicate that the pricing will come in closer to BRL26.00 per share."

Petrobras' board is expected to approve terms of the share offer later Thursday, with the company then releasing the results of its share offer after markets close.

At a range of BRL25.00 to BRL26.00, Petrobras is expected to raise between $68 billion and $74 billion--topping the previous record share sale of $36.8 billion raised by Japanese telecommunications company Nippon Telephone & Telegraph in 1987.