PARIS, June 30 (Reuters) - The French parliament on Friday adopted a watered-down version of a law once seen as posing a major threat to the future of online media stores like Apple's (AAPL.O: Quote, Profile, Research) iTunes Music Store in France.

The law, intended to counter the dominance of industry leaders like Apple or Microsoft (MSFT.O: Quote, Profile, Research) in online media stores, aroused bitter opposition in its original form and sparked suggestions Apple might pull its iTunes operation out of France.

In its initial form, the bill would have forced online media stores like Apple iTunes Music Store to drop barriers that prevent songs it sells being played on portable MP3 devices and computers designed to work with another music store.

At present, songs bought on Apple iTunes Music Store can only be played directly on Apple technology like the iPod player although they can also be burned onto CDs.

But after amendments introduced in the Senate, the law allows companies to argue that measures to restrict the technical compatibility of songs or films sold online were undertaken at the request of the authors.

The law, passed without a further reading after a special administrative measure from the Minister of Culture, was condemned by the opposition Socialists and several deputies in the ruling UMP party.

The Socialists said they would seek a ruling by the Constitutional Court.

But the government said it provided adequate rights for both consumers and operators.

"It will allow the development of legal services," Culture Minister Renaud Donnedieu de Vabres said.

Apple's iTunes service is currently the biggest online content store after the runaway success of the iPod player but it faces competition from several rivals including Sony Corp.