Republican Senator Josh Hawley of Missouri unveiled legislation on Monday aimed at strengthening antitrust laws and curbing the growing political power of America’s biggest companies. 

The legislation, which Hawley called “Trust-Busting For the 21st Century Act,” bans all mergers and acquisitions by companies with a market capitalization of over $100 billion, empowers the Federal Trade Commission (FTC) to prohibit “digital dominant firms” from buying out potential competitors, and forces companies that lose antitrust lawsuits to forfeit profits from monopolistic conduct.

“If you allow corporations to amass significant economic power through market concentration, they are going to have political power, and they’re going to use it,” Hawley told reporters. “We’re also seeing the growing political power, not just of tech, although that’s quite significant, but of industry across the board.”

Nearly 150 companies, including large corporations like Apple and Amazon, as well as others like Pfizer, Nike, Costco and McDonalds have a market cap of over $100 billion. All of them would be impacted by Hawley’s bill and prohibited from merging with or acquiring smaller competitors.

Hawley pointed to the more than 100 corporations that virtually met Saturday to signal their organized opposition to restrictive voting laws being passed across the country as an example of corporate overreach. 

“Their efforts to influence or outright stop voting laws in various states, this is indicative I think of the kind of very significant and growing political power that the largest concentrated corporations the mega corporations have in this country and are willing to use today,” Hawley added. “Today it is election integrity, tomorrow it will be something else. The point is that their political power is tracking their economic power.”

Hawley, a frequent critic of major technology companies, told reporters the “intent” of the bill is to also directly impact big tech companies. The “immediate effect,” he said, will be to prohibit them from buying up competitors or start ups.

“The intent is to try and spur competition to try and open up the market and to try and make room for new businesses, new startups, fresh competition,” he said.

The new legislation from Hawley, if enacted, would not impact previous mergers or acquisitions. But, Hawley signaled that he wants to see companies like Facebook, Google and Amazon broken up.

“I will watch for some additional proposals from me very soon that affect the current composition of Facebook and Google, and Amazon,” Hawley said.

There are several bills from both political parties in the Senate that address antitrust laws. 

Earlier this year, Democratic Senator Amy Klobuchar of Minnesota, who Hawley said he is willing to work with on this issue, introduced a bill that would require companies, instead of the government, to prove that acquiring a competitor would not reduce competition in the marketplace. Klobuchar told CBS News in March she believes there is bipartisan interest in the Senate to push for stronger antitrust law enforcement and increased oversight of big tech companies. 

Hawley’s proposal could face some backlash from fellow Republicans because he is pushing for changes to the consumer welfare standard. The standard, which is used by enforcers to determine if antitrust action is necessary, focuses on the surplus gains for consumers. Hawley’s bill would change the law so that it is evaluated with an eye towards the economic competition as a whole. 

Hawley, who was Missouri’s attorney general for two years and pursued antitrust cases against Facebook and Google, said the consumer welfare standard is not clear and “has proven difficult for antitrust enforcers to use.”

Republican Senator Mike Lee of Utah, the ranking member of the Senate antitrust subcommittee, supports the consumer welfare standard and has said that “any legislative attempt to replace or undermine the consumer welfare standard is a non-starter.”

Hawley claimed that Senator Lee’s views on antitrust changes as the circumstances evolve but added that he’s hopeful the overall structure of his bill will “push the conversation forward” with fellow Republicans.

“I think the fact that we’re seeing less and less true competition across industry, fewer new business starts, declining small businesses, that ought to be a concern to every Republican who believes in robust, free competition,” Hawley said. 

He added that Republicans should also be concerned about the “concentration of political power that always follows the concentration of economic power.”

Hawley’s bill will allow the FTC to label companies like Facebook, Google, and Twitter as “digital dominant firms” and prohibit them from acquiring potential social media competitors. Companies with that label will not be allowed to prioritize their own search results without explicitly disclosing that information. 

The senator said economic consolidation is an issue beyond the tech industry and is a concern in banking, pharmaceuticals, and publishing industries. He said he wants “bright line rules” that are easy for corporations to follow and easier for the government to enforce.

“I think the net effect of this will be a pro-competition approach to trust law and I hope that is something that conservatives who believe in robust competition in the free market will be able to get by,” Hawley said.