The Kardashian clan is (in)famous for hawking detox teas, waist trainers and clothing brands. But now one consumer advocacy group is challenging the family on their Instagram advertising practices.

Last week the group Truth in Advertising (TINA) sent a letter to the Kardashians, warning them that their sponsored posts were deceptive to their followings. Since the letter was sent, the family members have gone back onto Instagram and put “#ad” at the start of their most recent sponsored posts. However, they only disclosed that the advertising for 20% of their sponsored posts, according to TINA.

Yesterday, the organization filed a formal deceptive advertising complaint with the Federal Trade Commission (FTC). The FTC has guidelines about social media advertising, which TINA says the Kardashians are not upholding. Basically, if you’re advertising something online, it should be made crystal clear (preferably at the start of the post) that it is an advertisement. Kim, Kourtney, Khloe, Kendall and Kylie have a combined following of 300 million people. Ergo large masses of people are being exposed to advertising without even realizing it, TINA said in their complaint.

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However, what’s interesting about this whole debacle is that the Kardashians updated and altered the posts from smaller companies, but not large ones like Estee Lauder or Puma. According to TINA, “The willingness of the Kardashians/Jenners to alter their Instagram posts endorsing companies such as SugarBearHair suggests they would also fix other similarly deceptive posts if permitted to do so by the other companies they endorse. As such, it is apparent that the issue is with the companies, who continue to flagrantly ignore the law.”

Just because TINA filed a complaint doesn’t mean that the FTC will do anything about the Instagram posts. But TINA has a pretty well-documented relationship with the organization and a fairly high success rate. It remains to be seen if the complaint will affect the Kardashians or their sponsors more at the end of the day.

What do you think of the Kardashian family’s ads? Let us know @BritandCo!

(h/t BuzzFeed; photo via Jamie McCarthy/Getty Images)