(Adds additional ruling information, lawyer comment, bankruptcy petition, background, bond and share prices)
RIO DE JANEIRO Feb 19 (Reuters) - Brazil's Oleo e Gas Participações SA has won a final court ruling to add international financing unit OGX Austria GmbH to its bankruptcy filing, a lawyer for the company said on Wednesday.
The approval by the 14th Civil Part of the Rio de Janeiro-State Justice Tribunal addresses concerns that failure to include foreign subsidiaries in the bankruptcy petition could mean any restructuring plan approved by a Brazilian judge might be open to legal challenges in Brazil or abroad.
OGX Austria has sold $3.63 billion in bonds, the bulk of the parent's debt. The ruling also allows the inclusion of Oleo e Gas overseas unit OGX International.
"The decision recognized the needs of international commerce," said Marcio Costa, a lawyer for Sergio Bermudes Advogados in Rio de Janeiro which represents Oleo e Gas. "Beyond this, the joint filing confirms the legal structure prepared for the case."
Oleo e Gas stock fell 4.2 percent to 0.23 reais, on track for its sixth decline in seven days, in mid-afternoon trading in Sao Paulo.
The Rio de Janeiro oil company controlled by Brazilian tycoon Eike Batista filed for protection from creditors in Latin America's largest-ever bankruptcy filing on Oct. 30. The company, formerly known as OGX Petroleo e Gas Participações SA, filed a restructuring plan with the 4th Commercial Part of the Rio de Janeiro-State Justice Tribunal on Friday, Feb. 14.
Under that plan Batista will give up control of the company to creditors owed 11.2 billion reais ($4.63 billion) at the time of the bankruptcy filing. The amount it owes in reais has gone up since then because of the impact of a weaker Brazilian real on debts in U.S. dollars. The real has slipped 8.8 percent against the dollar since the filing.
The dollar value of Oleo e Gas's obligations has fallen for the same reason. It was $5.2 billion at the time of the filing.
OGX Austria has sold $1.06 billion of 8.375 percent bonds due in April 2022 ; and $2.56 billion of 8.5 percent bonds due in June 2018.
The 2022 and 2018 bonds trade at about 5 cents on the dollar according to Thomson Reuters prices.
Oleo e Gas's bankruptcy filing is case number 0377620-56.2013.8.19.0001 at the Rio de Janeiro-State Justice Tribunal.
($1 = 2.40 Brazilian reais) (Reporting by Sabrina Lorenzi; Additional reporting by Jeb Blount; Writing by Jeb Blount; Editing By Franklin Paul and Richard Chang)