Microsoft, picking itself up from a big antitrust defeat in federal court, has added new firepower to its legal team as it prepares for the appeals phase of the landmark lawsuit.

Microsoft said Monday it had retained lawyer Carter Phillips, the managing partner of the Washington, D.C., office of Sidley & Austin, to help with its appeal. Phillips, 47 years old, is a well-known specialist in Supreme Court appeals.

Last month, he argued and won a high-profile case in which the high court found that health-maintenance organizations and others can't be sued under federal law for giving doctors financial incentives to hold down costs. His firm also was on the winning side of a recent case in which the Supreme Court upheld the so-called Miranda rights of prisoners.

The first task for Phillips and his team will be to help Microsoft argue against Judge Thomas Penfield Jackson's June 20 order certifying the antitrust case for direct review by the Supreme Court. Microsoft would rather have the case heard by the federal appeals court in Washington, D.C., which has ruled in Microsoft's favor before.

First Supreme Court brief due
Microsoft is appealing Judge Jackson's order to break the company in two and impose tough business-conduct restrictions, which the judge said were necessary because of the company's illegal monopoly in the market for operating-system software. Microsoft's first brief is due at the Supreme Court July 26. If the court chooses not to hear the case, it will move back down to the appeals court.

The move to hire Phillips doesn't mean Microsoft is unhappy with its lead trial counsel, Sullivan & Cromwell, a Microsoft spokesman said. Sullivan's strategy has been second-guessed by some in the wake of Judge Jackson's harsh ruling and his subsequent comments questioning the credibility of Microsoft witnesses in the trial -- much of which was dominated by the government's star prosecutor, David Boies. It isn't clear how much independence Sullivan had in setting its own agenda in court.

"Carter will work with Sullivan & Cromwell on our filing with the Supreme Court and about the jurisdictional issue," said Microsoft spokesman Jim Cullinan. Asked if that was a reflection on Sullivan & Cromwell's work, he said: "Not at all."

Indeed, Mark Levy, another appellate specialist who worked with Phillips in the US Solicitor General's office in the early 1980s, said it isn't unusual for companies to bring in new counsel for high-stakes appeals. "It's often recommended that even lawyers who are competent in trial court bring in an appellate specialist when a case reaches the Supreme Court," said Levy, a partner with Howrey Simon Arnold & White in Washington. "The Supreme Court is a specialized tribunal, and people who have experience there bring something to the case."

'Too early to comment'
Later, he worked as an assistant to the solicitor general before moving into private practice.

In a brief e-mail exchange, Phillips said it was "too early to comment about any strategy for the appeal either to the Supreme Court or the Court of Appeals."

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