Aug. 30 (Bloomberg) -- California and five other states disagree with U.S. antitrust regulators over whether court oversight of Microsoft Corp. has improved competition for personal computer software and provided more consumer choices.

California and the other states told a federal judge overseeing Microsoft Corp.'s antitrust settlement that the accord has done little to bolster competition or dent Microsoft's monopoly over personal computer operating-systems software.

U.S. Justice Department officials, joined by New York and four other states, argued the decree fostered competition. Both sides filed reviews of the settlement today with U.S. District Court Judge Colleen Kollar-Kotelly in Washington federal court. She'll decide whether to impose new requirements on Microsoft after court supervision of the decree expires in November.

``There can be little doubt that Microsoft's market power remains undiminished,''' California state regulators said in the filing in federal court today in Washington.

Two other states, Utah and Florida, didn't sign the California brief. Mark Shurtleff, the Republican attorney general of Utah, said in an Aug. 23 telephone interview that he didn't plan to sign the document because he didn't agree with its conclusions.

``The consent decree did, in fact, change Microsoft's behavior,'' Shurtleff, said. ``Microsoft has done everything we have required of them.''

California and the other states will discuss with Kotelly what remedies are needed to address the settlement's deficiencies at a Sept. 11 hearing in Washington, said Kathleen Foote, California's senior assistant attorney general.

Justice Department View

Justice Department antitrust officials said court supervision of Microsoft Corp. has led to more competition and benefited consumers, in its filing in the same court. New York, Ohio, Louisiana, Maryland and Wisconsin joined the department in its filing.

``The final judgments have been successful in protecting the development and distribution of middleware products and in preventing Microsoft from continuing the type of exclusionary behavior that led to the original lawsuit,'' said Thomas O. Barnett, Assistant Attorney General in charge of the Department's Antitrust Division, in a statement.

Microsoft said the settlement has been a success.

``As it was specifically intended, the consent decree defined clear rules for how Microsoft competes without pre- ordaining winners in the technology marketplace,'' said Brad Smith, general counsel, in a statement. ``The consent decree shaped how we view our responsibilities and led us to adopt a set of voluntary principles that will continue to apply even after major parts of the U.S. antitrust ruling expire this November.

A federal appeals court six years ago found Microsoft illegally defended its Windows monopoly by taking steps to discourage computer makers from promoting a rival browser. Microsoft is barred by a court order enforcing a 2001 settlement from harming desktop software made by competitors.

Once the decree expires, Microsoft's changes to its Windows operating system won't be supervised by a committee of technical experts getting complaints and advice from rivals. The company also won't have to charge the top 20 computer makers a uniform price for Windows subject to a volume discount.

The case is U.S. v Microsoft, 98-1232, U.S. District Court (Washington).

To contact the reporter on this story: Karen Gullo in San Francisco at kgullo@bloomberg.net.

Last Updated: August 30, 2007 17:35 EDT