The Commission said the mismatch between U.S. and Luxembourg tax laws resulted in the U.S. fast food chain not paying any taxes on some profits.

"This decision strengthens Luxembourg's position that while the application of the rules in force at the time might have resulted in a situation that no longer reflects the current spirit of the national and international tax framework, such an application does not constitute state aid," Luxembourg Finance Minister Pierre Gramegna said in a statement.

(Reporting by Foo Yun Chee; editing by Philip Blenkinsop)