Industry leaders fingered directly in the suit include top brass from Netscape Communications Corp.

CNN: U.S. counties lodge class-action suit over Internet taxation

Firefox, first launched in 2004, was the first to loosen the hold over the market that Internet Explorer attained in the late 1990s after eclipsing Netscape Communications Corp.

WSJ: Google's Chrome Surpasses Firefox as No. 2 Browser to Internet Explorer

The court hearing stems from an anti-trust suit the US Government filed last October, accusing Microsoft of using its dominance with the Windows 95 operating system to gain an unfair market share for its Internet browser, Internet Explorer, over its competitor Netscape Communications Corp.

BBC: Microsoft lawyers meet opponents