AMD has asked a judge to protect the trade secrets of PC vendors so they can testify in the company's long-running antitrust lawsuit against Intel.

AMD filed a brief with its request earlier this week in US District Court in Delaware.

The move is part of a June 2005 lawsuit in which AMD claims that Intel uses overwhelming market share in the x86 microprocessor market to intimidate computer makers and retailers from buying AMD chips.

AMD has issued subpoenas for documents from 32 companies, including computer makers HP and Dell, and retailers Best Buy and Circuit City.

Some of those companies refused to share the documents, saying that would expose trade secrets such as manufacturing processes and capacity.

To break that logjam, AMD and Intel negotiated a "protective order" on 2 May that could keep the most sensitive testimony secret. AMD has now offered additional concessions.

Intel filed a similar brief on Tuesday, agreeing with some of the new terms. But Intel is reluctant to change as much of the original deal, insisting it had already made its best compromise. The two companies plan to file a joint brief on Thursday that summarises their positions.

If a judge approves it, the result would strike a balance between the subpoenaed companies' rights to protect their secrets and the US public's right to enforce open competition in the marketplace, AMD said in a statement.

For example, the order would grant confidentiality to testimony not only about microprocessors and chipsets, but also about PC and server manufacturing, and operating system and software design.

It would also allow time for each company to ask the court to seal any testimony before it is revealed in a courtroom trial.

In a separate part of this lawsuit, AMD filed a brief on Friday that refuted Intel's 3 May motion to dismiss the charges involving PC vendors based outside the US.

Intel said that US antitrust laws do not have jurisdiction over its business deals with Japanese computer vendors Sony, Toshiba, NEC, Fujitsu and Hitachi, and the European vendor Fujitsu-Siemens.

In response, AMD said that international boundaries are not relevant to 21st century commerce, which consists of a "single, global market for x86 microprocessors".