Arkansas, Idaho, Indiana, Kentucky, Mississippi, Missouri, North Dakota, South Dakota and Utah signed on to the Texas-led suit.

Key context: The suit comes amid increasing scrutiny in Washington of big tech firms and their dominance in a wide array of markets at the center of consumers’ everyday lives. The House Judiciary antitrust panel has called for a revamp of antitrust laws, and the FTC and a group of state attorneys general sued Facebook last week calling for it to be broken up.

This latest lawsuit is separate from an antitrust case that the Justice Department and 11 state attorneys general filed in October over Google’s power in the online search market. And more trouble for the company could arrive as soon as Thursday, when a different collection of states led by Colorado and Nebraska is preparing to file an additional suit against Google over its search dominance, as POLITICO reported Tuesday.

Google’s response: In a statement, Google said it would contest the allegations, which it called “baseless claims.”

“Attorney General Paxton’s ad tech claims are meritless, yet he’s gone ahead in spite of all the facts,” spokesperson Julie Tarallo McAlister said. “We’ve invested in state-of-the-art ad tech services that help businesses and benefit consumers. Digital ad prices have fallen over the last decade. Ad tech fees are falling too. Google’s ad tech fees are lower than the industry average. These are the hallmarks of a highly competitive industry.”

Google’s control: Google is the No. 1 player in the market for digital ads. Wednesday’s suit focuses on display advertising, the images, text and videos that often pay for websites like news, sports, blogs and smaller e-commerce sites.

Since its acquisition of DoubleClick in 2008, Google has systematically bought and built out its advertising technology portfolio and owns some of the most used tools that advertisers use to buy online ads and websites use to sell them. The company also operates an exchange to buy and sell ads in automatic transactions, similar to the way Wall Street traders now use algorithms to automate sales on stock exchanges.

The complaint alleges that Google used a variety of tactics to push both advertisers and website publishers to use its tools and exchange and took steps to undermine new innovations in the advertising technology ecosystem that could have supplanted its control. For example, the states allege that Google adopted a technology that helps mobile websites load more quickly, called Accelerated Mobile Pages, in part because it doesn’t work with certain types of ads used by its competitors.

Google maintains that the online advertising market is a crowded and competitive one. In testimony before a Senate panel in September, a Google executive noted that the company faces competition from other major players including Adobe, Amazon, AT&T, Comcast, Facebook, News Corp., Oracle and Verizon.

How we got here: In September 2019, states led by Paxton announced an antitrust probe into Google. The investigation initially focused only on Google’s control over advertising technology — an area where regulators in Australia, the U.K. and France had probed Google but so far taken only minimal steps to rein in the search giant’s power.

Over time, the state probe expanded into other aspects of Google’s business, including search and the mobile operating system Android. Texas continued to focus on the ad tech industry, while other states including Colorado, Nebraska and Iowa took the lead on other areas.

Texas has one of the biggest offices in the country devoted to antitrust issues. In the 1990s, the Lone Star State was among the first to probe Microsoft over antitrust concerns and in the 2010s opened a probe into Apple related to e-book price fixing before the Justice Department.

Delayed by Paxton scandal: Texas’ leadership role became more controversial in late September after seven top aides to Paxton accused him of abusing his office by doing favors for a Republican donor. The aides included Paxton’s No. 2, Jeff Mateer, as well as two other key figures in the Google probe. All three resigned, and Paxton fired or placed on leave the remaining four individuals.

Other attorneys general sought to distance themselves from Paxton, with Democratic attorneys general calling on him to resign to preserve the integrity of their “joint work,” but Paxton has refused to do so. Over the past two months, he and other Texas officials sought to get the Google case back on track. In early November, Paxton appointed Shawn Cowles as his new deputy for civil litigation to head up the suit.

On Tuesday, Texas announced that it had hired two law firms — the Lanier Law Firm and Keller Lenkner — to help litigate the case.

Where’s DOJ: Meanwhile, the Justice Department has pursued its own investigation into Google’s dominance in advertising technology. DOJ sued Google on Oct. 20 over the tech giant’s control of the online search industry but said its probe into advertising would continue.

Attorney General William Barr, a major force behind the DOJ’s Google probes and antitrust suit, had hoped to see the second Google case filed before the end of the Trump administration in January. But with Barr’s early resignation on Dec. 23, the decision will be up to Deputy Attorney General Jeffrey Rosen whether to follow in Texas’ footsteps and file an antitrust complaint against Google over ad tech, or leave it to President-elect Joe Biden’s new DOJ team.

What’s next: Texas’ suit was assigned to Judge Sean Jordan, a Trump appointee who joined the bench in 2019. Jordan served in the Texas Attorney General’s office from 2004 through 2012, but didn’t overlap with Paxton, who became attorney general in 2015.

The Justice Department’s own investigation into Google’s control over advertising technology remains ongoing.