Seven of the US states that successfully sued Microsoft over antitrust issues have asked for the original ruling to be extended until 2012.

The legal move has been started by California, Connecticut, Iowa, Kansas, Minnesota, Massachusetts and the District of Columbia, which are unhappy with Microsoft's delays in complying with the original ruling.

"Pursuant to the Modified Final Judgment and Rule 60(b) of the Rules of Civil Procedure [we] respectfully move the Court to extend expiration of all provisions of the Modified Final Judgment, except III.B, until November 12 2012, " the legal document states.

The plaintiffs are asking three of the five years to be added because Microsoft has failed to provide all the communications protocols from its software.

The document also noted that the original ruling has not yet led to full competition in the browser market, as "no major OEM currently distributes a browser other than Microsoft's Internet Explorer".

The states are also claiming that the competitive benefits currently derived from servers implementing the communications protocols are often dependent on the middleware.

"Given that Microsoft is just now delivering complete technical documentation after years of delay, during which it increased its share of the server market, it would be unreasonable to terminate the middleware-related provisions now," the document said.

The filing was completed by Kathleen Foote, a senior assistant attorney general for the State of California.

The seven states had already asked for government oversight to be continued for a further three years, as the original ruling expires in November this year.