Advanced Micro Devices (AMD) has filed a wide-ranging antitrust suit against Intel, accusing it of maintaining its monopoly in the PC processor market by illegally coercing customers around the world into using its products.

The suit, filed in the US District Court for the District of Delaware, identifies 38 companies on three continents that were allegedly coerced by Intel, including large-scale computer makers, small system builders, wholesale distributors and retailers, according to a statement from AMD.

The 48-page complaint alleges that Intel used illegal subsidies to win sales and, in some cases, threatened companies with "severe consequences" for using or selling AMD products.

A spokeswoman for Intel in Hong Kong said the company had yet to receive formal notice from AMD or the US courts about a complaint.

"We won't have any comment until we do," said Intel spokeswoman Laura Anderson.

Microprocessor monopoly

The case pits Intel's main rival against the world's largest manufacturer of microprocessors in what could be a long and tough legal fight.

AMD's litigation follows a recent antitrust investigation of Intel in Japan by the Fair Trade Commission of Japan (JFTC). In March, the JFTC found that Intel had abused its monopoly power to exclude fair and open competition in the Japanese microprocessor market. The result was to substantially restrain competition, the JFTC said.

Intel's Japanese subsidiary agreed in April to refrain from several types of business practices, although it also said it disagreed with the JFTC's findings.

The European Commission has also said it is pursuing an investigation against Intel for possible antitrust violations and that it was cooperating with the Japanese authorities.

AMD's complaint lists several examples of how Intel has allegedly abused its dominate market position. One of them claims that Intel forced major customers, such as Dell, Sony, Gateway and Hitachi, into exclusive deals in return for outright cash payments, discriminatory pricing or marketing subsidies.

Mari Hayashi, an AMD spokeswoman in Tokyo, said AMD would discuss the suit further in a conference call in the US.