The Federal Trade Commission is warning companies across the U.S that if they employ bogus endorsements or misleading reviews to lure customers, they should be prepared to face the consequences.

This week, the federal consumer body unanimously decided to send so-called notices of penalty offenses to more than 700 brands, reminding them of its enforcement powers and cautioning them that deceptive conduct could bring a civil penalty of up to $43,792 per violation.

“Fake reviews and other forms of deceptive endorsements cheat consumers and undercut honest businesses,” said Samuel Levine, director of the FTC’s Bureau of Consumer Protection, adding that companies “will pay a price if they engage in these deceptive practices.”

The list of companies receiving the FTC warning includes some of the country’s largest advertisers, including Ford, GM, Walmart, Target, Amazon, McDonald’s, Burger King, Mattel and Marriott.

Also receiving the same warnings this month were several major U.S.-based ad agencies including 72andSunny, BBDO, DDB, McCann Worldgroup, Saatchi & Saatchi and Wieden+Kennedy.

“This is a very significant development,” said Linda Goldstein, a partner at law firm BakerHostetler who co-leads its Advertising, Marketing and Digital Media team, citing the FTC’s notices as a “direct result” of a unanimous Supreme Court ruling in April that deeply restricts what kinds of monetary relief the commission can seek.

“The Supreme Court said in no uncertain terms” that the FTC cannot obtain monetary relief by going directly to federal court under section 13(b), Goldstein said, referring to a clause in the FTC Act that governs injunctions. “In reaction to that, the FTC has said that it will use any and all avenues available to obtain monetary relief in its enforcement actions,” which includes its penalty offense authority, she said.

Goldstein believes this week’s round of penalty notices may be “the first of many of these industry-wide sweeping letters,” calling it an “end-run” around the Supreme Court’s decision that may mark a lasting shift in how the FTC enforces its rules—although the move does not necessarily imply that the federal body will be doing more enforcement than in the past.

“The FTC has not used its penalty offense authority for as long as I can remember,” Goldstein said. “This is a huge warning signal to the entire advertising community that the FTC is going to be very aggressive in its enforcement actions in the future.”

A complete list of businesses that have been put on notice is available on the FTC’s website. The agency says, however, that just because a brand has received a notice does not mean it is accused of engaging in unfair or illegal conduct.

Deceptive practices that may be met with FTC enforcement include but are not limited to: “Falsely claiming an endorsement by a third party; misrepresenting whether an endorser is an actual, current, or recent user; using an endorsement to make deceptive performance claims; failing to disclose an unexpected material connection with an endorser; and misrepresenting that the experience of endorsers represents consumers’ typical or ordinary experience,” according to the agency.