Google parent Alphabet asked a U.S. federal judge Monday to dismiss a Justice Department lawsuit alleging that the search giant illegally abused its dominance of online advertising.

The government, which filed the ad tech lawsuit in January along with eight states, had argued that Google should be forced to sell its ad manager suite. Google has denied any wrongdoing.

"In the more than three years that it has been investigating Google's ad tech business, the United States has received more than two million documents from Google and taken over thirty depositions of Google witnesses," the company said in a court filing late Monday. "Yet plaintiffs remain unable to find support for their claimed antitrust harms."

Google argued that the case should be thrown out because the government had erred in defining the online advertising market and improperly excluded powerful competitors such as Facebook. It also said that the government's estimate of Google's ad exchange as having "more than 50%" of the market fell short of the 70% needed to allege market power.

The company also said the government was wrong to assert that Google's acquisitions of DoubleClick and AdMeld, both more than 10 years ago, harmed competition. Antitrust enforcers approved both transactions at the time.

Google urged a hearing to consider the motion to dismiss.

The case is being heard by U.S. Judge Leonie Brinkema in the Eastern District of Virginia.

The Justice Department's ad tech lawsuit follows a separate lawsuit filed in 2020, at the end of the Trump administration, that accused Google of violating antitrust law to maintain its dominance in search. That case goes to trial in September.

The Biden administration has sought to toughen antitrust enforcement. Alongside the Google suit, it also has a long list of merger challenges.

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