* ITC judge had ruled that patents were not infringed
* Full commission to consider the case
* Final decision is due in July
WASHINGTON, May 3 (Reuters) - A U.S. trade panel said Thursday it would review a decision made in March that chipmakers LSI Corp and STMicroelectronics NV did not illegally use Rambus Inc’s patented chip technology.
A judge at the U.S. International Trade Commission said in March that the companies did not violate Rambus’ patents for memory controllers, which retrieve information when it is needed, and high-speed chip-to-chip communication systems.
But the full commission said on Thursday that it would review the case. It is due to issue a final decision in July.
Rambus said in an emailed statement that it was “encouraged” by the decision to review the case.
The commission asked for briefings on a wide range of issues, including whether some of the patents should be deemed invalid because they are obvious.
Rambus had initially accused the companies of infringing on six patents but one of the six was dropped from the complaint.
In the last 12 months, Rambus settled patent litigation with Nvidia Corp, Broadcom Corp and Freescale Semiconductor Ltd. It reached a settlement agreement with MediaTek in March.
Three of the five patents at issue in this case - collectively known as the Barth patents - have been declared invalid by an appeals board at the U.S. Patent and Trademark Office. Two were declared invalid in September and a third in January.
But the patents remain valid during the appeals process, which has not yet been exhausted.
Rambus has aggressively used the three Barth patents to pursue infringement claims against technology companies.
Rambus’ share price has been volatile, sometimes rising and falling sharply depending on the results of its court fights.
In after-hours trade on Thursday, the stock it was just 1.5 percent higher at $4.80 from its $4.73 close on Nasdaq.
Rambus shares rose sharply in early February on news that it settled patent disputes with arch rival Nvidia. But its share price dropped almost 60 percent late last year after the company lost a $4 billion antitrust lawsuit against Micron Technology Inc and Hynix Semiconductor Inc.
The Rambus, LSI, STMicroelectronics NV case at the International Trade Commission is Number 337-753.