A bipartisan group of senators is taking aim at Google and Meta, introducing a bill that would break up the companies’ ad businesses.

Google and Meta are the dominant advertising platforms online, and both have been accused of anti-competitive behavior. Such behavior has increasingly drawn the scrutiny of regulators on both sides of the Atlantic, with a bipartisan group of senators ready to take action.

The Competition and Transparency in Digital Advertising Act (CTDA) has been introduced by Senator Mike Lee (R-UT), as well as Senators Amy Klobuchar (D-MN), Ted Cruz (R-TX), and Richard Blumenthal (D-CT). The bill would prohibit companies with more than $20 billion in digital ad transactions from owning more than one part of the ecosystem. This measure would address concerns aimed at Google, which is seen as controlling virtually all aspects of the online advertising industry.

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Similarly, smaller companies that process more than $5 billion in ad transactions would be required to meet certain criteria aimed at protecting both the competition and the consumer.

Senator Lee said, “Digital advertising is the lifeblood of the internet economy. It supports most of the free content and services Americans have come to rely upon, including essential local journalism, and it allows businesses of every size to reach their customers quickly and efficiently. Unfortunately, online advertising is also suffering under the thumb of trillion-dollar tech companies.

“Companies like Google and Facebook have been able to exploit their unprecedented troves of detailed user data to obtain vice grip-like control over digital advertising, amassing power on every side of the market and using it to block competition and take advantage of their customers. The conflicts of interest are so glaring that one Google employee described Google’s ad business as being like ‘if Goldman or Citibank owned the NYSE.’”

Needless to say, Google is calling foul on the new bill, telling The Verge that it is “the wrong bill, at the wrong time, aimed at the wrong target.” The company then went on to blame “low-quality data brokers” for the issues targeted by the bill.

It remains to be seen if the bill will pass, although its early bipartisan support is certainly something of an indicator. The bill is also the latest evidence of regulators’ growing impatience with Big Tech, and what they perceive as abuses of its power and influence.