The US Patents and Trademarks Office has ruled in favour of Canadian tech firm i4i in its patent suit against Microsoft.
i4i claimed that Microsoft had made use of one of its patents in the software giant's Word software.
The US Patent and Trademarks Office issued a re-examination certificate to the company for its patent, meaning that it has confirmed that i4i owns the rights to the disputed technology.
The patent review was conducted after a request from Microsoft.
In 2007, i4i had sued Microsoft for infringing on its patent related to the XML editor used in Word.
In August 2009, a US district court had ruled in favour of i4i and ordered Microsoft to pay $290 million in damages and legal fees and remove Word from the market within 60 days.
The company is now planning to appeal against the decision to the US Supreme Court, but experts believe that the company is unlikely to receive a different verdict.
Loudon Owen, i4i chairperson, said: “Put simply Microsoft lost the trial, lost the appeal, and lost the re-examination.”