Netscape, a subsidiary of AOL, filed a lawsuit against Microsoft late yesterday, alleging that the software maker harmed Netscape with anticompetitive practices related to the Windows operating system.

This is, essentially, the lawsuit that Netscape has been waiting for, as it's based on the rulings by the US government against Microsoft last year.

AOL's latest lawsuit was filed in the US Federal District Court for the District of Columbia, according to a statement from Netscape.

Microsoft's illegal anticompetitive practices were confirmed in a ruling by a federal district court in June 2000 and upheld by a US appeals court in June last year.

Best known for its Netscape Navigator web browser, Netscape was acquired by AOL in 1999. AOL merged with Time Warner last year.

Netscape argues in its lawsuit that those anticompetitive practices "resulted in harm to competition and antitrust injury to Netscape in particular", the company said in its statement.

Netscape is seeking an injunction against Microsoft and an award of "treble damages", a type of award given in a private US antitrust case that would be equal to three times any damages set by a court.

The value of the damages and any Microsoft products that might be enjoined from shipping as a result of the suit would be determined by a federal judge, the company said.

The injunction Netscape is seeking resembles a settlement offer submitted in December 2001 by the nine US states that have yet to agree on settlement terms with Microsoft.

That offer included restrictions on how Microsoft would be able to sell Windows to consumers and PC makers.

The lawsuit includes seven counts alleging that Microsoft used illegal anticompetitive behavior to harm Netscape. The alleged pattern of behavior started in 1995, when Microsoft began promoting its own Internet Explorer browser in a way that Netscape argues was detrimental to the Netscape browser.