HRT Slumps After Romeu Replaces Founder Mello as CEO: Rio Mover

HRT Participacoes em Petroleo SA, the Brazilian oil and natural gas explorer focused mainly on the Amazon and Namibia, dropped the most in more than eight months after its founder and chief executive officer resigned.

The stock tumbled 17 percent to 3.80 reais at the close in Sao Paulo, the most since Aug. 31. The Rio de Janeiro-based company is down 83 percent since its Oct. 25, 2010 initial public offering.

Marcio Mello, who founded HRT as an oil-service company before transforming it into an oil and gas explorer, announced his resignation on May 10, after markets closed. Mello had stepped down as chairman of HRT April 4, after the company’s board split the position from the CEO position. He will be replaced by Milton Romeu Franke, HRT’s head of engineering, drilling and production, according to a statement released today.

HRT has failed to find oil in the Amazons, as Mello has repeatedly said it will, and has yet to find crude off the coast of Namibia. The company last week announced the $135 million acquisition of BP Plc’s 60 percent stake in the offshore Polvo field in Brazil, which produces about 13,000 barrels of oil a day and will provide the company with revenue.

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