United States District Courts are the trial courts of the federal court system and they settle the disputes brought before them. They exercise their jurisdictions within the light of the Constitution of the United States of America, federal statutes, acts, and treaties. They also perform their duties in civil and criminal cases. In the 11 th edition of the Model Courts of Justice, the United States District Court, more precisely the Columbia Circuit, would deliver its judgment regarding one of the landmark cases in antitrust law ‘Microsoft Corporation v. United States of America’. In this case, it will be discussed that Microsoft had violated or not violated the related provisions of the Sherman Act concerning the monopolization on the Operating Systems and tying agreements with the Original Equipment Manufacturers.