The Department of Justice (DOJ) and Google gave their final arguments on Monday in an antitrust case regarding Google’s digital advertising technology.
U.S. District Judge Leonie Brinkema is expected to make a decision by the end of the year.
DOJ’s Argument
The DOJ claims that Google has built and kept a monopoly in open-web display advertising through products like DoubleClick, Google Ads, and AdExchange.
They say Google holds about 91% of the market for publisher ad servers and 87% for advertiser ad networks.
The case against Google is supported by a 2009 email from former Google executive David Rosenblatt. He mentioned the company’s goal to “do to display what Google did to search.”
Prosecutors argue that this shows Google’s plan to control the digital advertising market.
Another important part of the trial is Google deleting internal chat messages. Google claims most of these were casual chats but admitted that some included business discussions.
Google’s Response
Google is challenging the DOJ’s definition of the advertising market.
DOJ sees digital advertising as three separate markets:
Ad servers
Ad exchanges
Advertiser ad networks
Google argues digital advertising is a two-sided market:
Buyers of digital ads
Sellers of digital ads
By that definition, Google competes with social media companies, like Meta and TikTok, and streaming services.
When considering these competitors, Google claims its market share is only about 10%.