The technology patents at the heart of an infringement lawsuit by NTP against Research in Motion, the seller of the BlackBerry wireless e-mail device, are likely to be struck down by the U.S. patent office, both companies have said, a move that would be a setback for NTP.

The U.S. Patent and Trademark Office took the unusual step of notifying the companies that it expected it would 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.

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

The patent review, which was requested by Research in Motion, is a proceeding separate from a patent infringement lawsuit that could potentially shut most BlackBerry service in the United States early next year.

Judge James Spencer of U.S. District Court, who is overseeing the infringement case, has set a timetable for hearings on issuing an injunction against Research in Motion that could coincide with the timing of the patent office's final rulings.

The patent office document was sent with a letter dated last Wednesday in which the office introduced an accelerated timetable for the review and promised extra staff resources for the examination.

"It was a resounding rejection of NTP's position," James Balsillie, Research in Motion's chairman and co-chief executive, said by telephone. "The jig is up. I think the world is now starting to realize what is happening."

Donald Stout, a patent lawyer and NTP's co-founder, said he did not believe that the case was nearly over. He acknowledged, however, that the company fully expected that its patents would be overturned by the patent office.

Balsillie said his lawyers believed that any hearings for an injunction halting BlackBerry service would be immediately put on hold if the patent office makes its rejections final.

In Research in Motion's view, NTP would be able to move forward only if it were able to regain its patents through appeals, a process that could take years.

Stout and lawyers for NTP said the two processes were wholly separate, and that an injunction against Research in Motion remained a possibility. "We're not going to go away silently," Stout said. "Unless the case is settled, it keeps on going."