A Luxembourg-based unit of Yukos had a claim against Rosneft thrown out by the Moscow District Federal Arbitration Court, Interfax reported late Thursday.

The court upheld a May 18 ruling by the Moscow Arbitration Court overturning a decision by the International Commercial Arbitration Court, which last year ruled in favor of a 13 billion ruble ($510 million) claim by Yukos Capital S.a.r.l., Interfax said.

At the time, Yukos Capital won four lawsuits to recover debts from loans it made to Yuganskneftegaz, Interfax said.

Yuganskneftegaz was once Yukos' largest production unit before Rosneft acquired it in 2004.

Yukos' court-appointed bankruptcy manager Eduard Rebgun said Friday he wants to stay with the company for an extra six months because his job is not finished.

Rebgun petitioned the Moscow Arbitration Court to extend his position by six months after it expires on Aug. 1, one year after the court declared Yukos bankrupt, Rebgun's spokesman Nikolai Lashkevich said in an e-mailed statement Friday.

Rebgun needs the extra time because two bankruptcy sales remain later in August and the liquidation of the company is not complete, Lashkevich said.