Europe revokes Rambus chip patent

The European Patent Office (EPO) revoked one of Rambus Inc.’s European patents on computer memory chip technology Thursday, in response to opposition from rival chip makers.

The decision by the EPO’s Technical Board of Appeal does not affect the Los Altos, California, company’s other European patents, or its U.S. patents, Rambus said. The company is awaiting a ruling Tuesday in an unrelated case concerning its U.S. patents.

The revoked patent, number 0 525 068, related to a technology called “an access time register” and was effective in Germany, France, the U.K. and Italy.

As is its practice, the EPO has not yet given a reason behind its decision to revoke the patent. That will be revealed when the agency releases its written decision in four to ten weeks, Rambus said. The EPO is a centralized body that grants patents to states contracted to the European Patent Convention. Twenty-seven European states currently participate.

In a statement released Thursday Rambus said that although the ruling was a disappointment it is “a small part of a larger picture” and it looks forward to reading the EPO’s written decision.

Rambus filed for the European patent in 1991 and opposition was filed against it in 2000 by Micron Europe Ltd., Micron Technology Italia S.R.L. and German-based companies Infineon Technologies AG, Hynix Semiconductor Deutschland GmbH and Micron Semiconductor Deutschland GmbH. In response, the EPO amended the patent in November of 2002, but that decision was appealed, leading to Thursday’s decision to revoke the patent.

Rambus has been entangled in a series of U.S. lawsuits involving its patent claims on memory chip technology and faces a decision Tuesday by the U.S. Federal Trade Commission (FTC) on whether it practiced unfair competition by allegedly deceiving a standards-setting body into adopting the memory technology in order to profit from licensing fees.

In addition to its case with the FTC, Rambus is also involved in a patent suit over memory chip technologies with Infineon which is expected to go to trial May 10, according to an Infineon spokesman.

The Infineon spokesman said Friday that the company was pleased with the EPO’s decision, adding that Rambus has “no basis for all related claims to its patent infringement suit against Infineon.”

Asked whether he thought the ruling would affect the U.S. case between the two companies, he said it would be up to the court to decide.