Sen. Josh Hawley (R-Mo.) introduced legislation Tuesday that would condition legal protections for online platforms that utilize behavioral advertising, the use of browsing habits to serve tailored ads to users.

The Behavioral Advertising Decisions Are Downgrading Services (BAD ADS) Act would take Section 230 protections away from the biggest tech companies that use the advertising method.

Section 230 of the 1996 Communications Decency Act, which has come under increased scrutiny since President Trump targeted it in an executive order in May, gives internet companies immunity from lawsuits for content posted on their sites by third parties and allows them to make “good faith” efforts to moderate content.

The law is considered foundational for online companies, and the threat of having it revoked has increasingly been proposed as a cudgel to compel platforms to make changes by lawmakers.

Only companies with either 30 million users in the U.S. or 300 million worldwide and $1.5 billion in global revenue would be affected by Hawley’s bill.

“Big Tech’s manipulative advertising regime comes with a massive hidden price tag for consumers while providing almost no return to anyone but themselves,” Hawley said in a statement.