MOUNTAIN VIEW, Calif.-- Rambus Inc. here today announced it has added Samsung Electronics Co. Ltd. to its list of DRAM companies agreeing to license patented technologies for SDRAM, double data rate (DDR) memories, and controllers interfacing to those chips. The South Korean memory giant joins Japan's NEC, Toshiba, Hitachi, and Oki in paying extra royalties for those Rambus patents.

During the summer, Rambus stirred up a legal controversy when it began negotiating new licensing pacts for patents on high-speed synchronous DRAMs, DDR chips, and controllers. The company is also promoting its own Direct Rambus memory format as a competitor to DDR memories for high-bandwidth storage in new computers, with the backing of Intel Corp.

While five DRAM companies have agreed to license Rambus' synchronous DRAM technologies, Micron, Infineon, and Hyundai are separately fighting the Mountain View company in court. Micron Technology Inc. in Boise, Idaho, claims Rambus is violating U.S. antitrust laws and unfairly attempting to force licensing agreements for SDRAM interfaces.

Rambus has been accused of using information from industry standards meetings to take advantage of DRAM suppliers that are preparing to ship high volumes of DDR memories. Rambus officials dispute those claims.

Under the new Samsung licensing agreement, Rambus will collect royalties for DDR SDRAM and the controllers at a higher rate than what it gets for Direct Rambus memories. The agreement also includes royalties for SDRAM and for controllers that directly interface to SDRAM, as well as a license fee for the entire agreement, according to Rambus, which has struck the same terms with NEC, Toshiba, Hitachi, and Oki.

The agreement with Samsung gives Rambus royalties for SDRAMs from the world's largest suppliers of memory chips. The Korean company's DRAM sales in 1999 totaled $4.8 billion, or 20.7% of the world's market, according to Dataquest Inc.

"We have had a long and mutually beneficial relationship with Samsung," said Geoff Tate, chief executive officer of Rambus. He also added that the licensing campaign is part of Rambus' efforts to generate a return on investments in technology innovations, which then benefit the company's shareholders.

"We believe our RDRAM memory interface is the best solution for the majority of the market," the CEO added. "Developing and marketing the RDRAM memory interface has been and remains our top priority. But we are willing to license our IP for other memory interface solutions as well."

Rambus' stock took a major hit in trading on Tuesday, following an EBN news story that said Intel was dropping Direct Rambus DRAMs from every computing platform but high-end workstations by the middle of 2001 (see Oct. 30 story). Rambus stock fell 15.9% in trading Tuesday after recovering from more than a 25% drop in the middle of the day, closing at $44.94 per share, a drop of $8.50.