WASHINGTON, Sept 9 (Reuters) - Two patents that chip designer Rambus (RMBS.O) used to win patent lawsuits against Nvidia Corp (NVDA.O), Hewlett-Packard (HPQ.N) and others have been declared invalid by the U.S. Patent and Trademark Office, according to legal documents.
The patents are two of three known as the Barth I patents, which Rambus has used in suing high-tech companies. Rambus’ share price varies sharply on its successes in patent litigation.
The International Trade Commission, which hears patent litigation involving imported products, had ruled in July 2010 that graphics chip maker Nvidia, Hewlett-Packard Co and other smaller companies had infringed those two patents as well as a third.
Nvidia settled with Rambus on the issue.
The patent office in early September notified Rambus that two of the Barth I patents were invalid. Despite the ruling, the patents will remain valid if Rambus appeals the rejection to the U.S. Court of Appeals for the Federal Circuit.
“We are confident in the validity of our patents and are exploring our next steps to seek reversal of these decisions,” Rambus said in an emailed statement.
A decision on the third patent is expected within months, said Scott Daniels, a patent attorney with Westerman, Hattori, Daniels and Adrian, LLP.
The patents were also among six that Rambus used in accusing a long list of companies of infringing in a new ITC complaint filed about nine months ago. That complaint was filed against Broadcom BRCM.O, STMicroelectronics and MediaTek (2454.TW), among others.
Rambus, which is based in Sunnyvale, California, is also locked in a $4 billion antitrust battle against memory chip makers Hynix Semiconductor Inc (000660.KS) and Micron Technology Inc (MU.O) in a California state court.
Rambus says South Korea’s Hynix and Idaho-based Micron colluded to fix prices of memory chips used in personal computers and prevent its technology from becoming widely used. (Editing by Gary Hill)