Micron Technology Inc. has made a last-minute bid to intervene in the Rambus Inc. SDRAM patent infringement trial against Infineon Technologies AG, according to documents released by the Federal District Court in Richmond, Va.
Micron has its own SDRAM patent suit against Rambus pending in the Federal District Court in Wilmington, Del., slated to begin May 31. Both Infineon and Micron are raising charges that Rambus by failing to disclose its SDRAM patent applications misled the industry JEDEC committee that was drafting an open standard on the memory chip.
Both also allege that Rambus filed its specific SDRAM patent claims years after the JEDEC standard on SDRAM was adopted.
Rambus denies the charges and claims an original patent application filed in 1990 for its Rambus DRAM covers features found in SDRAM chips.
The Richmond court docket also disclosed that Federal Judge Robert Payne upheld an Infineon motion to bar supplemental testimony by Rambus' expert witness, William Huber, on whether Rambus 1990 patent application concerning a Rambus DRAM multiplex bus covered SDRAM which instead has three separate memory bus lines.
Judge Payne has ruled previously that the Rambus patents cover only a multiplexed memory bus. In pretrial hearings, Judge Payne questioned if Dr. Huber was "flip-flopping" trying to supplement earlier expert testimony on Rambus patents after the judicial ruling narrowly defining the SDRAM patent coverage.