The U.S. Department of Justice on Tuesday joined attorneys general from several states in filing an antitrust lawsuit against Google parent Alphabet. The complaint alleges that the company has monopolized key digital advertising technologies that website publishers and online advertisers rely on for their basic economic survival. 
“Today’s complaint alleges that Google has used anticompetitive, exclusionary, and unlawful conduct to eliminate or severely diminish any threat to its dominance over digital advertising technologies,” said Attorney General Merrick B. Garland. 
The complaint outlines anti-competitive practices over a 15 year period.  Per a DOJ press release, these include:  
  • "Acquiring Competitors: Engaging in a pattern of acquisitions to obtain control over key digital advertising tools used by website publishers to sell advertising space;
  • Forcing Adoption of Google’s Tools: Locking in website publishers to its newly-acquired tools by restricting its unique, must-have advertiser demand to its ad exchange, and in turn, conditioning effective real-time access to its ad exchange on the use of its publisher ad server;
  • Distorting Auction Competition: Limiting real-time bidding on publisher inventory to its ad exchange, and impeding rival ad exchanges’ ability to compete on the same terms as Google’s ad exchange; and
  • Auction Manipulation: Manipulating auction mechanics across several of its products to insulate Google from competition, deprive rivals of scale, and halt the rise of rival technologies."
“In pursuit of outsized profits, Google has caused great harm to online publishers and advertisers and American consumers," said Deputy Attorney General Lisa O. Monaco. "This lawsuit marks an important milestone in the Department’s efforts to hold big technology companies accountable for violations of the antitrust laws.”
This isn't the first time the Justice Department has taken aim at Google. The department filed a civil lawsuit in 2020 against its monopoly practices in search and search advertising. 
Correction: Changed day from 'Wednesday' to 'Tuesday.'