PARIS (Reuters) - France's antitrust agency is investigating Microsoft ( MSFT ) over concerns that it is degrading the quality of results when smaller rivals pay to use Bing technology in their own search-engine products, Bloomberg reported on Monday.

The competition authority declined to comment, citing a policy of not publicly speaking about investigations that were underway. A Microsoft ( MSFT ) spokesperson did not immediately respond to a request for comment.

The investigation could lead to formal charges and a fine against the U.S. tech giant.