United States v. Microsoft was the biggest antitrust case of the early internet era. The government accused Microsoft of using its control of Windows to crush competition in web browsers. A judge ordered the company split in two, an appeals court threw out the breakup, and the case ended in a settlement that shaped how the tech industry competed for the next decade.
If an older article or encyclopedia sent you here, the original Microsoft case archive from this site is preserved in the Internet Archive: view the archived page. You can also browse more early internet law cases.
What Happened
In the mid-1990s, Netscape Navigator was the most popular way to browse the web. Microsoft, whose Windows software ran most personal computers, built its own browser, Internet Explorer, and began tying it to Windows. It also struck deals with computer makers and internet providers that made it hard for them to favor Netscape.
In May 1998, the U.S. Department of Justice and 20 states, along with the District of Columbia, sued Microsoft. They claimed Microsoft illegally protected its Windows monopoly by bundling Internet Explorer and pressuring business partners, because a popular independent browser could have made Windows less important. Microsoft said it was simply improving its product and competing hard.
What the Courts Decided
After a long trial, Judge Thomas Penfield Jackson found in 1999 and 2000 that Microsoft held a monopoly and had broken the antitrust laws to keep it. In June 2000, he ordered Microsoft split into two companies, one for Windows and one for its other software.
In June 2001, the federal appeals court in Washington, D.C. agreed that Microsoft had illegally maintained its monopoly but threw out the breakup order. It also sent the case to a new judge, in part because Judge Jackson had discussed the case with reporters while it was pending. The Justice Department and several states settled with Microsoft in late 2001. The settlement required Microsoft to share certain technical information with competitors and barred some of its deals with computer makers. Other states pressed on, and the court largely adopted the same terms.
Why It Mattered
The case showed that technology companies are not exempt from antitrust law, and that controlling a key piece of software can be a monopoly in the legal sense. Some commentators credit the restrictions it placed on Microsoft with making room for a new generation of internet companies, including Google, which grew up while Microsoft was under court supervision.
Big Tech in Court Today
Today the largest tech companies face a new wave of lawsuits. Some are antitrust cases like Microsoft’s. Others are very different: thousands of families are suing Meta, TikTok, Snap and Google, claiming the companies designed Instagram, Facebook, TikTok, Snapchat and YouTube to keep children hooked despite knowing the harm to young users.
Those lawsuits seek compensation for children, teens and young adults who developed depression, anxiety, eating disorders or self-harm after heavy social media use. If your child was harmed, Doyle APC handles these claims together with experienced co-counsel. Learn more about the Meta lawsuits or see who may qualify.
Common Questions
What was United States v. Microsoft about?
The government claimed Microsoft illegally protected its Windows monopoly, mainly by tying its Internet Explorer browser to Windows and pressuring computer makers and internet providers not to favor the rival Netscape browser.
Was Microsoft broken up?
No. A trial judge ordered a breakup in 2000, but the appeals court threw out that order in 2001 while agreeing that Microsoft had broken the antitrust laws. The case ended in a settlement instead.
When did the case end?
The Justice Department settled in late 2001, and the court approved the settlement in 2002. Court supervision of Microsoft under the settlement lasted until 2011.
Why does the case still matter?
It remains the leading example of the government using antitrust law against a dominant technology company, and it is frequently compared with today’s cases against Google, Meta and other tech giants.
Who runs this site now?
Doyle APC, a San Diego law firm that represents people nationwide in mass tort cases. Doyle APC handles social media addiction claims together with experienced co-counsel. Learn more about the firm.