Rambus has won the latest round in its four-year battle to collect royalties from memory chips makers which use patented Rambus high-speed memory interface technology in their products.
The US Supreme Court denied a request to review an appeal's court decision which favoured Rambus over German company Infineon Technologies. The semiconductor maker disputes Rambus' claims that it is entitled to collect the royalties in question.
The case will now go back to the lower court for a new trial.
"Today's rulings help substantiate the importance of our past inventions and allow us to continue our focus on technology leadership," said Rambus chief executive officer Geoff Tate.
Infineon said it will be ready for the new trial.
In May 2001, a court threw out all Rambus' claims of patent infringement against Infineon related to SDRAM (synchronous dynamic random access memory) and DDR SDRAM (double data-rate SDRAM). This decision was a response to the lawsuit Rambus had filed against Infineon.
That court also found Rambus guilty of fraud for obtaining patents on chip designs standards which were being developed at the time by the memory standards group JEDEC (Joint Electron Device Engineering Council), of which Rambus was a member, and fined the company $3.5m. This decision was in response to an Infineon countersuit.
In October 2001, the court later refined its decisions on the Infineon countersuit, reducing the fraud fine to $350,000 and determined that Rambus had committed fraud with regards to SDRAM but not with regards to DDR SDRAM. The lower court also forbade Rambus from pursuing litigation in the US against Infineon's JEDEC-compliant SDRAM memory products
The court's actions were a blow to the crusade Rambus had launched in early 2000 to collect royalties from its SDRAM and DDR SDRAM patents.
However, the appeals court's decision in January 2003 deflated Infineon's victory by confirming the breadth of Rambus' patent claims, which the court had narrowed, and determining that Rambus had committed no fraud.
Infineon's attempt to have the court's decision restated died yesterday when the Supreme Court refused to review the appeals court's decision. Now Rambus' patent infringement claims will be retried at the lower court. Infineon's fraud allegations will not be retried, because the fraud verdict was reversed by the appeals court.
However, Rambus is still not out of the water on the JEDEC fraud allegations. The US Federal Trade Commission has charged the company with deceiving the JEDEC to profit from licensing fees. That case is being heard by an FTC administrative law judge tomorrow.
Rambus began its crusade in January 2000 when it sued Hitachi, alleging that the company had infringed on Rambus' high-speed memory interface technology in Hitachi semiconductor products featuring SDRAM and DDR SDRAM. Rambus wanted the court to forbid Hitachi from manufacturing, selling or importing chips featuring the patented technologies. The technologies in question had, until then, been made available to all manufacturers free of royalties.
Rambus scored a huge victory six months later when Toshiba agreed to sign a licensing deal with it and to pay royalties to Rambus regarding this issue.
About a week later Hitachi also relented and agreed to a licensing deal. In August 2000, Rambus confirmed it was having talks related to this issue with all major makers of SDRAM, seeking licensing agreements. The following month it signed a licensing agreement with NEC, and in November 2000 with Samsung Electronics.
However, not everybody agreed to Rambus' demands, including Infineon, Hynix Semiconductor and Micron Technologies, the three of which opted separately to fight Rambus in court to try to invalidate its patent claims.
A variety of legal actions have been taken since then by Rambus and its counterparts both in the US and Europe. The Infineon tussle is widely seen as the one that will make or break Rambus' claims. In November 2001, a US court postponed a lawsuit by Hynix pending the resolution of the Rambus appeal against Infineon.
Rambus also develops a memory interface called Direct RDRAM (Rambus dynamic random access memory), although it has not filed any legal claims on its licensing.
Juan Carlos Perez writes for IDG News Service