Hynix Semiconductor said Thursday that a U.S. court ruled in its favor against Rambus Inc., a U.S.-based technology licensing firm, in an antitrust law violation battle.

The judge in the San Francisco court rejected allegations filed by Rambus that Hynix and Micron Technology were involved in a conspiracy ― manipulating the price of their memory chips and violating California’s antitrust law.

“We welcome the decision reached by the court in the end of the first round and we will give our best efforts to let the company’s voice be heard in case of an appeal,” a Hynix official said.

Rambus could file for an appeal at the higher court within 60 days of the first ruling.

In May 2004, Rambus filed a lawsuit against the two chipmakers at the San Francisco court, requesting that the two firms pay $3.95 billion in royalties. Rambus said its RDRAM had been thrown out of the market due to their conspiracy.

If Hynix and Micron had lost the suit, the antitrust damage costs might have tripled up to $11.9 billion, according to jury precedent.

However, nine of 12 jurors ruled that Micron and Hynix were not involved in a plot to interfere Rambus’ businesses and that they were also not engaged in price-fixing of computer chips.

Hynix has also won a patent infringement appeal against Rambus earlier in May that had been ongoing for over a decade.

The ruling had overturned its previous ruling, which enabled Hynix not to pay the hefty compensation it had been ordered to pay in 2009.

Industry watchers said it was a watershed moment for not only the Seoul-based company, which has been mired in the legal battle with Rambus for over a decade, but also for other chipmakers against which Rambus has filed similar lawsuits.

A U.S. court in March 2009 had ruled in favor of Rambus in a case alleging that Hynix infringed on 15 Rambus patents related to DRAM, dynamic random access memory chip technology.

Hynix was subsequently ordered to pay $397 million to Rambus as compensation, in addition to paying royalties to the California-based firm.

Hynix, however, appealed the court decision a month later.

By Cho Ji-hyun (sharon@heraldcorp.com)