NEW YORK - Rambus Inc shares fell more than 15 percent on Tuesday after a San Francisco judge pushed back a key antitrust case involving the chip designer until next year.

The trial, which was set to start Sept. 28, was set to pit Rambus against Micron Technology Inc (MU.N), Hynix Semiconductor Inc (000660.KS) and Samsung Electronics Co Ltd (005930.KS). Rambus said it was delayed to Jan. 11, 2010.

Rambus has accused the companies of engaging in price- fixing and hurting sales of its RDRAM memory chips, which are used in computers.

Capstone Investments analyst Jeff Schreiner said in a note to clients the California state-level trial was delayed due to the grave condition of a Samsung attorney.

Rambus spokeswoman Linda Ashmore said San Francisco Superior Court Judge Richard Kramer decided to delay the start of the trial beyond the 30 days requested by Samsung due to concerns about keeping a jury during the Thanksgiving and Christmas holidays.

A Samsung spokeswoman was not immediately available for comment.

The delay may have disappointed investors, who had been encouraged after a court denied requests by Micron and the other memory makers to look at prior rulings on the case. The stock had risen about 13 percent in the past month.

Schreiner repeated his strong buy rating on Rambus saying he saw little impact in the final outcome of the trial, which could be worth more than $12 billion in damages.

We believe Rambus's case remains intact, and see no change in legal position, he said.

Rambus shares fell 15 percent to $16.30 in morning trading on Nasdaq, where it was one of the most active issues.

The case is Rambus Inc vs. Micron Technology Inc in the San Francisco Superior Court of California, case no. CGC-04-431105. (Reporting by Franklin Paul and Alexei Oreskovic; editing by Derek Caney and Andre Grenon)

California Electronics Update