Hynix said it believes the ruling will "substantially limit" the royalties it will be required to pay Rambus for infringing on the company's patents.

Judge Ronald Whyte of the U.S. District Court for the Northern District of California said in his ruling, which was dated September 21, that Rambus' patents should still be seen as valid.

Still, Rambus' destruction of evidence "should preclude it from entitlement to a royalty that places Hynix at a competitive disadvantage," Judge Whyte wrote in his ruling.

Both companies have been ordered to submit briefs to the court on what they believe would be a reasonable royalty rate for the patents.

"This is a positive result as it is consistent with what we've been seeking all along - reasonable compensation for the use of our patented inventions," Rambus General Counsel Thomas Lavelle said in a statement.

The same judge had previously ordered Hynix to pay Rambus around $397 million for infringing on dynamic random-access memory (DRAM) patents.

(Reporting By Michael Erman; Editing by Daniel Magnowski)

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