LANSING, Mich. (WLNS) – Michigan has joined 16 other states in a lawsuit against Google for allegedly monopolizing digital advertising technologies for the past 15 years.

The alleged monopolization has resulted in the elimination of competition across digital advertising markets.

These technologies, known collectively as the “ad tech stack,” are key tools on which website publishers and advertisers rely to buy and sell ads and reach potential customers.

Google’s alleged actions are in violation of multiple sections of the Sherman Anti-Trust Act of 1890.

“The power that Google wields in the digital advertising space has had the effect of either pushing smaller, less ubiquitous companies out of the market or making them beholden to Google ads to market their clients’ products,” Michigan Attorney General Dana Nessel said in a press release this week.

“This is monopoly behavior and I’m glad to join the DOJ lawsuit to loosen Google’s grip of digital marketing and make it more equitable for small businesses,” Nessel continued.

The lawsuit was filed in January by the U.S. Department of Justice, along with the Attorneys General of California, Colorado, Connecticut, New Jersey, New York, Rhode Island, Tennessee, and Virginia.

“We allege that Google has captured publishers’ revenue for its own profits and punished publishers who sought out alternatives,” U.S. Associate Attorney General Vanita Gupta said in January.

“Those actions have weakened the free and open internet and increased advertising costs for businesses and for the United States government, including for our military.”

Along with Michigan, other states joining the DOJ lawsuit this week are Arizona, Illinois, Minnesota, Nebraska, New Hampshire, North Carolina, Washington and West Virginia.