Japan's fair-trade watchdog is set to issue a warning against U.S. software giant Microsoft Corp., which has been under investigation on suspicion of violating the country's antimonopoly law, an official said Friday.

But the U.S. software giant won't be fined, the official said.

The Fair Trade Commission has decided to issue the largely symbolic warning against Microsoft next week, a commission official said on condition of anonymity.

The commission raided Microsoft's Japan offices in February as part of an investigation into the software giant's contracts with manufacturers. The contracts allegedly contained restrictive conditions that would prevent patent infringement lawsuits.

Microsoft has said it is dropping the clause in its new contracts, although it maintains the provision is legal under Japanese, U.S. and European Union laws.