OTTAWA, Dec. 19 - The technology patents at the heart of an infringement lawsuit by NTP against Research In Motion, the maker of the BlackBerry wireless e-mail device, are likely to be struck down by the United States patent office, both companies said on Monday, a move that would be a setback for NTP.

The United States Patent and Trademark Office took the unusual step of notifying the companies that it expected to reject the five patents held by NTP in its final rulings.

The office has issued preliminary rejections of all five wireless e-mail patents in the past. The final rulings may come by mid-February, earlier than expected.

"The patent owner's arguments are deemed nonpersuasive," said the patent office document, which was received last week but dated Nov. 30. "The next office action is expected to be a final rejection of all current claims."