Hitachi strikes back at Rambus over patent claims

Hitachi Ltd., countering patent-infringement charges leveled by Rambus Inc., is accusing the memory technology company of improperly developing its patents based on information obtained during meetings to develop industry standards.

The Tokyo-based electronics company has asked the federal court in Wilmington, Del., to invalidate Rambus patents to synchronous chip technology. Hitachi claims Rambus improperly revised after attending industry meetings aimed at developing open standards for semiconductor development.

The industry-standard meetings were overseen by the Joint Electronic Devices Engineering Council (JEDEC).

"Instead of participating in the JEDEC standard-setting process in good faith, Rambus subverted the process," Hitachi claimed in a March 24 filing. "Rambus improperly revised its pending (patent) applications ... to cover what it learned from its participation in JEDEC and the disclosures of other JEDEC members and participants."

Hitachi also accused Rambus of violating federal antitrust laws by forcing companies that license its technology to follow "Rambus-dictated specifications" that prevent manufacturers from using non-Rambus products and alternative technologies.

In addition, Hitachi filed a motion to have the case moved from Wilmington to a federal district court in California, where Hitachi Semiconductor America and Rambus are based.

Rambus filed suit against Hitachi in January. In its filing, the Mountain View, Calif., company accused Hitachi of violating four 1990 patents that "cover fundamental technology relating to synchronous memory devices and methods of controlling such devices."

On Feb. 29, Rambus filed two more infringement claims based on patents that were issued that day. Rambus alleges that its patents are infringed by certain Hitachi SDRAMS and logic chips, including Hitachi's SH series microprocessors.

In addition, Rambus has asked the U.S. International Trade Commission to bar the import of certain Hitachi memory and microprocessor products into the United States.

The products named in the suit do not involve RDRAM (Rambus dynamic RAM) specifications. Hitachi has licensed RDRAM technology but has not produced Rambus products.

In its countersuit, Hitachi claims that Rambus filed its initial patent suit only after an industry alliance of Intel Corp. and the industry's five largest DRAM makers announced plans to develop a synchronous DRAM interface technology as an alternative to Rambus' RDRAM interface.

Rambus designs, develops and licenses high-bandwidth chip-connection technologies aimed at enabling semiconductor memory devices to keep pace with faster generations of processors and controllers. Its technology is licensed to more than 30 semiconductor companies, including Intel.