United States v. Microsoft Corporation, 253 F.3d 34 (D.C. Cir. 2001), was a landmark American antitrust law case at the United States Court of Appeals for the District of Columbia Circuit. The U.S. government accused Microsoft of illegally maintaining its monopoly position in the personal computer (PC) market, primarily through the legal and technical restrictions it put on the abilities of PC manufacturers (OEMs) and users to uninstall Internet Explorer and use other programs such as Netscape and Java.