The United States Department of Justice (“DOJ”) and three overlapping groups of states have filed federal antitrust cases alleging Google has monopolized internet search, search advertising, internet advertising technologies, and app distribution on Android phones. In this Article, we focus on the DOJ’s claims that Google has used contracts with tech firms that distribute Google’s search services in order to exclude rival search providers and thus to monopolize the markets for search and search advertising—the two sides of Google’s search platform. The primary mechanisms of exclusion, according to the DOJ, are the many contracts Google has used to secure its status as the default search engine at all major search access points. The complaint echoes the DOJ’s claims two decades ago that Microsoft illegally maintained its monopoly in personal computer operating systems by forming exclusionary contracts with distributors of web browsers, and by tying its Internet Explorer browser to Windows. The gist of the case was that Microsoft had used exclusionary tactics to thwart the competitive threat Netscape’s Navigator browser and Sun Microsystems’ Java programming technologies—both forms of “middleware”—posed to the Windows monopoly. In this Article, we argue that the treatment of market definition, exclusionary contracting, causation, and remedies in the D.C. Circuit’s Microsoft decision has important lessons for the Google litigation.
John E. Lopatka and William H. Page, The Microsoft Litigation’s Lessons for United States v. Google, 77 U. Mia. L. Rev. 319 (2023).