Tensilica patent claims voided

The claims, which underlie Tensilica's approach to generating tools for configurable processors, were deemed either to be covered by prior art or to not represent a patentable advance.

An anonymous party — allowed under U.S. patent law — filed the request to re-examine 41 claims of the patent through Berkeley, Calif., patent attorney James Isbester last May. The Patent Office assigned the re-examination to Leigh Garbowsky.

In the request, Isbester cited three papers, all published before the keystone patent application was filed, that were believed to cover 41 claims in the patent. Garbowsky last month rejected those 41 claims and went on to reject the remaining 63 claims in the patent, citing the papers named in the request for re-examination.

The action is just the beginning, rather than the last word, of the negotiation process that attends patent filings. A spokeswoman for Tensilica said that such requests happen all the time in advanced technology, and that the company does not regard this as anything unusual.

"We are preparing our response to the examiner," she said. Until there is a final finding, Tensilica will continue to hold the patent, but will not be allowed to move against anyone for violating it, the spokeswoman said.

Attorney Isbester confirmed that requests for re-examination are not unusual, and in fact are generally granted if properly filed. Approximately 80 percent of re-examinations result in confirmation of at least some of the claims examined, he said.

"The examiner will search for prior art," Isbester said. "If he or she finds something, there will be discussion between the examiner and the claimant." The claim may then be narrowed, but "rarely does it result in a patent being revoked altogether."