Western Digital Says Patent Suit Settled : Litigation: Cadtrak Corp. had alleged that the Irvine company had violated patents on computer-graphics circuit boards and microchips.

Western Digital Corp. said Tuesday that it has settled a patent-infringement lawsuit with Cadtrak Corp. in which Cadtrak had accused the Irvine firm of violating patents on computer-graphics products.

Cadtrak, a small computer-graphics firm in San Mateo, sued Western Digital in June, 1990, claiming that the Irvine electronics company was violating patents on computer-graphics circuit boards and microchips. Under the settlement, Western Digital will make no payments to Cadtrak and Cadtrak has agreed to dismiss the suit, said Robert Blair, a Western Digital spokesman. Western Digital will also have a license to use Cadtrak technology as it pleases, he said.

“I don’t think there could have been a more favorable settlement for Western Digital,” Blair said.

A spokeswoman for Cadtrak declined comment.

Western Digital had previously contended that the Cadtrak claim lacked merit and that its computer-graphics subsidiary in Brisbane, Calif., held a valid license for the Cadtrak technology involved in the patent dispute.

Western Digital entered the computer-graphics business by acquiring Paradise Systems in 1986 and Verticom in 1988.

The Irvine firm contended that Pardise and Verticom had purchased licenses in lump-sum payments from Cadtrak before the Western Digital acquisition and that the licenses could be transferred legally.

More than 250 computer companies have agreed to pay royalties for the right to incorporate Cadtrak’s patented features in their product designs. Royalties are usually 2% of revenue.

At the time it filed its lawsuit, Cadtrak notified Western Digital customers that the graphic boards and graphic-controller chips that it supplies were not licensed. But Western Digital reaffirmed on Monday that the customers are protected.

“Many of our customers have been monitoring this suit closely, and will be pleased that the license covering our chips protects them,” Ilene Graney, a Western Digital vice president, said in a statement.

Cadtrak was founded to market a high-end engineering workstation, but the product was pulled from the market in 1986 and the company has since focused solely on licensing its patents.