The US Department of Justice has an filed antitrust lawsuit against Google over the company’s dominance in the ad technology space (via Reuters). The DOJ is joined in its lawsuit by the US states of California, Colorado, Connecticut, New Jersey, New York, Rhode Island, Tennessee, and Virginia.

The complaint follows a previous antitrust DOJ lawsuit about Google’s efforts to maintain its leading position in the search engine market. This lawsuit was filed in October 2020 under the Trump administration, and the case is expected to go to trial in September 2023.

In this new lawsuit, the Justice Department claims that Google has violated the Sherman antitrust act. It asks the court to order the divestiture of the Google Ad Manager suite, including Google’s Doubleclick for Publisher ad server and the company’s ad exchange AdX.

“Google’s anticompetitive behavior has raised barriers to entry to artificially high levels, forced key competitors to abandon the market for ad tech tools, dissuaded potential competitors from joining the market, and left Google’s few remaining competitors marginalized and unfairly disadvantaged,” the Justice Department said in the antitrust complaint.

As a result of Google’s dominance over the ad tech market, the DOJ pointed out that “website creators earn less, and advertisers pay more, than they would in a market where unfettered competitive pressure could discipline prices and lead to more innovative ad tech tools that would ultimately result in higher quality and lower cost transactions for market participants.”

In a statement shared with Reuters, a Google spokesperson said that “DOJ is doubling down on a flawed argument that would slow innovation, raise advertising fees, and make it harder for thousands of small businesses and publishers to grow.”

Even though Google is mostly known for its search engine, Chrome browser, and Android mobile OS, it is, first and foremost, an ad company: Google currently makes 80% of its revenue from advertising, and even though it’s being challenged by Facebook and other companies, it certainly deserves scrutiny from the US government.