A London court threw out Aeroflot's $23 million lawsuit against exiled tycoon Boris Berezovsky on Tuesday.
The airline was seeking damages for money that Russian prosecutors say Berezovsky and his business partner Nikolai Glushkov stole in the 1990s.
A Moscow court sentenced Berezovsky to six years in prison and ordered him to pay the airline 215 million rubles in 2007.
Aeroflot has already seized several million dollars worth of assets in repayment, and announced its intention to file suit in London to recover the rest of the money in April.
But Judge Christopher Floyd in a written judgement Tuesday declined to enforce the request.
"The decision to reopen the [Moscow] judgment as to the amount of damages payable was a plain breach of the finality principle," Floyd wrote.