Microsoft Corp was ordered to pay $388 million in damages for infringing a patent held by anti-piracy software maker Uniloc Inc on Wednesday.

Microsoft, the world's largest software maker, said it was disappointed in the verdict, and plans to appeal.

The verdict was reached by a jury in a long-running case in federal court in Rhode Island, which found that Microsoft infringed Uniloc's patent on software that generates unique identities for licensed users and prevents unauthorized use or copying of programs.

We believe that we do not infringe, that the patent is invalid and that this award of damages is legally and factually unsupported, said a Microsoft spokesman. We will ask the court to overturn the verdict.

Uniloc USA and its Singapore-based parent originally filed suit against Microsoft in 2003, claiming that Microsoft infringed its patent with security software it was using to prevent unlicensed use of its Windows XP operating system and parts of its Office suite of products.

After six years of legal wrangling, the jury trial started in March. The damages award is one of the largest on record in patent law disputes.

The case: Uniloc USA, Inc., et al v. Microsoft Corp., et al, U.S. District Court District of Rhode Island (Providence), 1:03-cv-00440-S-DLM.

(Reporting by Bill Rigby; Editing Bernard Orr, Gary Hill)

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