More than 30 states brought an antitrust lawsuit against Google on Thursday, marking the third time in two months that government officials have sued the tech behemoth.

This newest complaint, brought in U.S. District Court for the District of Columbia, alleges that Google “has systematically degraded the ability of other companies to access consumers.”

“Google, one of the largest companies in the world, has methodically undertaken actions to entrench and reinforce its general search services and search-related advertising monopolies by stifling competition,” the states allege in a 115-page complaint.

The lawsuit is led by attorneys general from Colorado and Nebraska, who were joined by attorneys general from 34 other states, Puerto Rico and Guam. It comes one day after 10 attorneys general filed a separate antitrust lawsuit against Google, and two months after the U.S. Department of Justice sued the company.

The states that sued Thursday allege that Google grew its already dominant market share by arranging for its search engine to be the default option on many browsers and on Android devices.

While that allegation is similar to one made by the Justice Department in October, the states’ complaint also includes claims that Google restricts how some businesses that operate vertical search engines — like companies that aggregate travel-related information — appear on Google’s search results pages.

Those claims focus particularly on listings in “OneBox,” which the complaint characterizes as “a Google feature that appears prominently on the search results page to steer consumers to Google’s own properties.”

“Google discriminates in its OneBox policies for the purpose of excluding specialized vertical providers that present a threat to its monopoly power, as evidenced by Google’s differing treatment of specialized vertical providers operating in different verticals,” the attorneys general allege.

Google’s Adam Cohen, director of economic policy, said in a blog post that the company’s decisions about how to display listings stems from a desire to improve search results.

“When you search for local products and services, we show information that helps you connect with businesses directly and helps them reach more customers,” Cohen writes. “This lawsuit demands changes to the design of Google Search, requiring us to prominently feature online middlemen in place of direct connections to businesses.”  

He adds that other regulators, including the Federal Trade Commission, rejected claims made in the lawsuit filed Thursday.

In 2013, the Federal Trade Commission cleared Google of allegations that it violated antitrust laws by promoting its own offerings — like Google Maps — in the search results. At the time, former FTC Chairman Jon Leibowitz said the agency concluded that Google’s primary reason for touting its own offerings in the search results was “to improve the user experience,” as opposed to harming potential competitors.