Kardashian Jenner Productions, the California-based production company run by Kris Jenner that manages the Kardashian and Jenner family, did not immediately respond to request for comment.

Truth in Advertising’s letter was also sent to the 27 companies that the group suspects paid the Kardashians and Jenners for their posts, including major brands such as Calvin Klein, Estée Lauder, Puma, and Revlon’s Sinful Colors, none of which immediately responded to Quartz’s requests for comment. As of Monday evening, Truth in Advertising hadn’t gotten replies from any of the brands either. Patten said that three of the Kardashian sisters—Kim, Khloe, and Kylie—had edited their Instagram posts for the brand SugarBearHair, however.

This is not the first time the Kardashians have run into problems with social media ads. Kardashian West came under fire from the Federal Drug Administration last August when she posted an Instagram ad for a morning sickness pill that failed to disclose the risks associated with the medication. She also didn’t make it clear that the post was an advertisement, but the FTC didn’t sanction her. The incident occurred two months after the FTC first released its updated disclosure guidelines for social media endorsements. And Kardashian replaced the post with a new ad that met both the FDA’s and the FTC’s disclosure requirements. Scott Disick, the father of Kourtney Kardashian’s children, also bungled an Instagram sponsorship with an embarrassing copy-and-paste mishap in May.

Shortly before the FTC announced it would get tougher on social media disclosures, Snapchat stars started labeling their sponsored snaps as ads, per the FTC rules.

The FTC, the US agency tasked with protecting consumers, recently updated its rules to address a changing media and advertising landscape—one where “influencers” like the Kardashians can reach millions of followers with one click.

“We’ve been interested in deceptive endorsements for decades and this is a new way in which they are appearing,” an FTC official told Bloomberg earlier this month. “We believe consumers put stock in endorsements and we want to make sure they are not being deceived.”

The social media stars Kim Kardashian and Kylie Jenner had 80.4 million and 72.3 million followers, respectively, as of August 22. Patten at Truth in Advertising says that puts these young women’s online profiles in the same league as a major brand’s presence.

“They really are similar to larger companies with their following and marketing influence,” said Patten at Truth in Advertising, who is also an attorney. ”It’s time for the FTC to really start looking at some of these very large powerful social media influencers.”

Ted Murphy, CEO of IZEA, an internet marketing service in Winter Park, Florida, which works with social influencers, says this is easier said than done.

“Unfortunately, celebrities are some of the worst offenders of the FTC Guidelines,” Murphy said. “Many times this is at the direction of their manager or sponsor and the celebrities themselves have no idea that what they are doing could lead to legal action against them.”

That creates the potential for deceptive posts. “Fans have a right to understand what posts are sponsored,” he said. “If the Kardashians have received any form of compensation from the 27 companies listed in the Truth in Advertising complaint that should have been disclosed within those posts.”

Other experts say celebrities don’t take the FTC’s endorsement guidelines seriously because regulators rarely crack down on misleading posts. The FTC has filed complaints against a handful of brands including Warner Bros. and Lord & Taylor for not disclosing paid social posts. It recently told Bloomberg that it would get tougher on paid posts that weren’t clearly marked as ads.

The FTC doesn’t have access to all the contracts between brands and social media influencers, which makes it difficult to determine when someone is being paid for a post. When it can, it typically goes after the brands, not the celebrities.

There’s little incentive for celebrities like Kim Kardashian to label posts as ads because they’re typically paid for the posts irregardless, said Brian Salzman, CEO and founder of relationship marketing agency RQ Media Group, which works with AirBnB, Samsung, Google Play, and YouTube. “Honestly, I think it’s the brands’ responsibility to ensure that they do it,” he said. “I don’t think the brands have enforced it contractually.”

Truth in Advertising hopes its latest effort can change that.

The hope is that its campaign focused on the Kardashians could have a chilling effect on deceptive influencer marketing. The investigation was Truth in Advertising’s first into the Instagram practices of high-profile celebrities, and the group plans to look at others. “We’re not going to stop at the Kardashians,” Patten said. 

Though even if the Kardashians comply with the group’s demands, some have pointed out that taking down deceptive posts days or weeks later has little effect—since social media posts are mostly seen and engaged with in their first couple of hours live.

Updated at 1pm ET: This post was updated with a link to the Kardashian and Jenner family posts identified in the investigation, which was not available when the story initially published.

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