United States v. Google/Conclusions of Law/Section 3
III. MONOPOLY POWER: ADVERTISING MARKETS
The court now moves from search to advertising. Plaintiffs collectively assert that Google has monopoly power in three overlapping advertising markets. These markets and their relationships are illustrated below. U.S. Plaintiffs allege the broadest proposed market, search advertising, which includes all advertisements served in response to a query, regardless of the digital platform. Within the search ads market, Plaintiff States define a general search advertising market that includes only ads served on GSEs. Finally, both sets of Plaintiffs propose a general search text advertising market, limited to text ads appearing on a GSE’s SERP. Google counters that Plaintiffs’ proposed markets do not comport with business realities. There is, according to Google, one omnibus market for digital advertising, and the markets as alleged exclude various digital ad types that are effective substitutes for Google’s text and shopping ads.
The court considers each of Plaintiffs’ proposed markets under the Brown Shoe factors, and, to the extent that it recognizes a market, determines whether Google has monopoly power within it. The court addresses the broadest market first (search advertising), followed by the narrowest (general search text advertising), and then concludes with the one in between (general search advertising). It finds as follows. First, although there is a relevant product market for search advertising, Google does not monopolize it. Second, general search text advertising is a relevant product market in which Google has monopoly power. Finally, a relevant product market for general search advertising does not exist.