``America's anti-trust laws do not provide any basis for government regulators to design software products,'' Gates wrote in a letter to the magazine in response to an article it had published earlier. The letter was posted on the magazine's Web site.

State and federal governments sued Redmond, Washington-based Microsoft last month, arguing that the company had a monopoly in the operating system for personal computers and had used it to compete unfairly.

The lawsuit accused Microsoft of using Windows, the crucial operating software on most of the world's personal computers, to seize control of the software market for browsers to access the Internet. Microsoft has denied the charges.

Critics have claimed Microsoft uses its dominance in computer operating systems to try to drive other companies, such as NetscapeCommunications Corp, out of business.

``Contrary to the government's central accusation, Microsoft planned the integration of Internet technology into Windows well before Netscape was even formed, and long before it shipped its first browser in October 1994,'' Gates said in the letter. ``The fact that our browser was integrated into Windows 95 from the outset did not in an way prevent consumers from choosing another browser,'' he said.