Overview
Microsoft operating-system monopoly lawsuits (United States v. Microsoft, 1998–2002) form the benchmark U.S. antitrust case of the PC era. The DOJ and 20 states alleged Microsoft unlawfully maintained a monopoly in Intel-compatible PC operating systems and tied its Internet Explorer browser (per the trial court findings). In 2000 the district court ordered a breakup; the D.C. Circuit affirmed liability in part and vacated the remedy in June 2001, and the case settled in 2001–2002 with conduct remedies (per court records). We publish the case as a landmark reference; it is closed with no new intake.
Status of the science / claims: An antitrust case: the claims concerned monopoly maintenance in Intel-compatible PC operating systems and tying of the Internet Explorer browser (per the courts’ findings).
Companies involved
Settlement amounts
The case ended in a conduct-remedy settlement, not a monetary award (per court records, 2002). No payout amount applies; the matter is closed.
Key dates
- November 1, 2002Final settlement judgment entered with conduct remedies (per court records)
- June 28, 2001D.C. Circuit affirms liability in part, vacates breakup remedy (per the appellate opinion)
- April 3, 2000Court finds Microsoft maintained a monopoly and orders breakup (per trial court findings)
- May 18, 1998DOJ and 20 states file antitrust case against Microsoft (per court records)
Updates
- Updated Nov 1, 2002New landmark (Sep 2026): US v. Microsoft (1998–2002) — liability affirmed by D.C. Circuit; breakup vacated; conduct-remedy settlement (per court records).
Notable filings
No notable filings recorded yet. Docket entries are added from public court records as they appear.
FAQ
What was United States v. Microsoft?
A 1998 antitrust case in which the DOJ and 20 states alleged Microsoft monopolized the PC operating-system market and tied its browser (per the trial court findings).
Was Microsoft broken up?
The 2000 trial court ordered a breakup, but the D.C. Circuit vacated that remedy in 2001 and the case settled in 2001–2002 with conduct remedies (per court records).
Why is this case relevant today?
United States v. Microsoft is the reference point for modern platform monopolization cases, including the DOJ’s actions against Google and Apple (per court records and reporting).
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