It's common for manufacturers of cars, video game consoles, and other products to insist that consumers will void their warranty if they use unauthorized repair services or unauthorized third-party parts. Some even insist that you'll void the warranty if you break the "warranty seal."

These policies are illegal, according to the Federal Trade Commission.

On Tuesday, the agency announced it had sent warning letters to six companies for violating a 1975 law governing manufacturer warranties.

Who does the FTC have in mind? The agency doesn't name the six companies that were targeted in this enforcement action, so we don't know for sure. But the FTC does provide examples of warranty terms that violate the rules, and with a little Googling it's easy to figure out likely suspects:

Hyundai's warranty states that "the use of Hyundai Genuine Parts is required to keep your Hyundai manufacturer’s warranties and any extended warranties intact."

Nintendo's warranty states that "this warranty shall not apply if this product is used with products not sold or licensed by Nintendo."

Sony's warranty states that "this warranty does not apply if this product... has had the warranty seal on the PS4™ system altered, defaced, and removed."

These exact phrases, with names of companies redacted, are provided as examples in the FTC's release.

“Provisions that tie warranty coverage to the use of particular products or services harm both consumers who pay more for them as well as the small businesses who offer competing products and services,” said Thomas B. Pahl, acting director of the FTC’s Bureau of Consumer Protection, in a Tuesday statement.

The FTC is demanding that the companies stop voiding warranties and remove statements from their websites and other materials threatening to do so within 30 days.

As Motherboard's Jason Koebler explained a couple years ago, warranty-voiding policies are rampant in the consumer electronics industry:



Now the FTC says these kinds of policies are illegal. The FTC has initiated enforcement actions against other industries that void warranties in the past, but this appears to be the first time the FTC has specifically called out makers of cell phones and gaming consoles for the practice.

In recent years, a number of state legislatures have considered "right to repair" legislation to further bolster rights under federal law, but these bills have generally faced opposition from manufacturers.