The lawsuit, filed in Alexandria, Virginia, argues that Google has established dominance in the advertising technology sector by controlling both the supply and demand sides of ad transactions. The government asserts that this dominance allows Google to retain a significant portion of advertising revenue, which raises concerns about fair competition in the market.

During the opening statements, the DOJ emphasized the detrimental impact of Google's alleged monopolistic practices on publishers. They highlighted the case's potential to force Google to divest parts of its advertising technology business, which could have far-reaching implications for the company's revenue streams.

Google's legal team has countered the government's claims, arguing that the case is based on outdated perceptions of the internet. They maintain that advertisers are increasingly turning to alternative platforms, which undermines the assertion of Google's monopoly. Google also contends that any regulatory intervention could inadvertently benefit other large tech companies.

The lawsuit follows a recent ruling where a judge deemed Google's search engine a monopoly. The ongoing scrutiny from regulators worldwide indicates a growing concern over Google's market practices, particularly in relation to digital advertising, where competition is perceived to be stifled.