London-based intellectual-property company BTG Plc. announced Tuesday that it has filed suit against the companies in the U.S. District Court for the Northern District of California.

BTG alleges that Apple's and Microsoft's operating systems, as well as Microsoft's Office application suite, incorporate technologies covered by U.S. Patent No. 6,557,054, granted in April 2003.

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In a separate lawsuit in the same federal court, BTG subsidiary BTG International Inc. also sued Microsoft for patent-infringement over its active windows and offline browsing technologies in Windows.

BTG International, of West Conshohocken, Pa., accuses Microsoft of infringing on three U.S. patents dating from September 2000 to December 2003. They are patent Nos. 6,125,388, 6,611,862 and 6,658,464.

Neither officials from Microsoft nor from Apple could be immediately reached for comment.

Click here to read about Microsoft's FAT patent, which is under review.

In both lawsuits, BTG is seeking an unspecified amount of damages and an injunction against future use of the technologies. The company said in a statement that the lawsuits resulted from Microsoft and Apple not "entering into licensing agreements on commercially reasonable terms."

BTG said it holds a license to all of the patents from owner Teleshuttle Technologies LLC. Teleshuttle Technologies and parent company Teleshuttle Corp. are also named as plaintiffs in the lawsuits.

Richard Reisman, the inventor named on the patents, is the president of New York-based Teleshuttle, which calls itself a developer of e-media and e-business technology and a provider of consulting services.

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