The power of social media as a marketing tool has not escaped brands, celebrities — or The Federal Trade Commission.

Last month the FTC issued warnings to celebrities who plugged products on their Instagram accounts without clearly identifying their relationships with brands. The letters were meant to “educate” the celebrities on how to post without violating the organization’s disclosure guidelines.

WWD has obtained the 90 letters sent to 45 celebrities, their agents and the brands they were publicizing. Top celebrities included Sean Combs, Naomi Campbell, Sofia Vergara, Heidi Klum, Victoria Beckham, Allen Iverson, Lindsay Lohan, Kourtney Kardashian, Scott Disick, Zendaya, Jennifer Lopez and Akon. In the fashion, beauty and retail space, letters were sent to Adidas, Chanel, Lorac Cosmetics, Chiara Ferragni Collection, Cabela’s, Johnson & Johnson, Eos Products, Matisse Footwear, Yves Saint Laurent and Puma. Many of the posts in question have been taken down by the influencers either at the request of the brands or their agents. A full list of celebrities and brands appears below.

The FTC said it sent out similar letters to each influencer to “call attention” to the post in question. Each letter reads: “The FTC’s Endorsement Guides state that if there is a ‘material connection’ between the endorser and the marketer of a product — in other words, a connection that might affect the weight or credibility that consumers give the endorsement — that connection should be clearly and conspicuously disclosed, unless the connection is already clear from the context of the communication containing the endorsement. Material connections could consist of a business or family relationship, monetary payment, or the provision of free products to the endorser.”

The organization explained that disclosures, which commonly takes the form of #ad in a post, should be “clear” and conspicuous” and use “unambiguous language” that “stands out.” The FTC cited cases in which disclosures appeared in captions at the bottom of a post, and were only found if consumers clicked on the “more” button to reveal the full text. Multiple hashtags, tags and links also were frowned upon, as they obscure the disclosure.

For further clarity, the FTC enclosed two endorsement guides, which address ethical issues about credibility and whether accepting free products means influencers need to disclose that relationship to fans. In most cases, the FTC tends to err on the side of disclosure, even for athletes who are known ambassadors of brands.

The issue becomes murky when influencers are merely sharing that they are a fan of a particular product or brand. To that, the FTC says: “If you write about how much you like something you bought on your own and you’re not being rewarded, you don’t have to worry.”

But in a handful of the cases, the FTC still insists on clarity. For instance, Victoria Beckham, who was sent a letter, posted about the brand Lancer Skin Care. The designer is pictured with its Contour Décolleté product and writes: “Loving this new contour by Décolleté by my friend @drlancerrx kisses from Los Angeles us X vb.”

Here, the FTC advocates for Beckham to disclose whether she has a financial or other business relationship with Lancer Skin Care, even though she refers to Dr. Lancer as a friend. Lancer aside, such posts may be difficult to police and create a slippery slope where influencers, brands and perhaps media companies and editors are put under a microscope.

Influencer Letter recipient (Brand) Jen Selter and Nicky Jam Mark King, president of Adidas NA Sean Combs Hal Kravitz, ceo Aquahydrate Shay Mitchell John Nosek, president of Kao USA Ciara and Dorothy Wang Jeremy Joseph, president and general counsel of Buscemi Luke Bryan Thomas L. Millner, ceo Cabela’s Kristin Cavallari John Galantic, president and chief operating officer Chanel USA Lucy Hale Riccardo Pozzoli, cofounder of Chiara Ferragni Collection Naomi Campbell Albert Bitton, cofounder The Clean Program Corp. Giuliana Rancic Alex Gorsky, chairman and ceo of Johnson & Johnson Sofia Vergara Dana Gordon, ceo Dana Rebecca Designs Heidi Klum Nigel Travis, ceo Dunkin’ Brands Group Rach Parcell Sherry Jhawar, director of Smooth Strategies, Eos Products LLC JWoww and Jamie Lynn Spears Daniel and Michael Broukhim, coceos, cofounders of FabFitFun Maci Bookout McKinney Joede Grant, owner J Gran Enterprise LLC Nicole Polizzi and Tiona Fernan Jack Ross, chairman, ceo Synergy CHC Corp. Amber Rose Samira Asemanfar and Melody Godfred of Fred and Far Vanessa Hudgens Anthony Fletcher, ceo of Nature Delivered Valentina Vignali James Hill, founder of Hairburst Limited Lilly Ghalichi Leyla Milani-Khoshbin, Khosh Milani Enterprises Caroline Manzo Dominik Richter, ceo of Hello Fresh AG Allen Iverson Rilwan Hassan, IO Moonwalkers Inc. Behati Prinsloo Josie Maran, founder and chief empowerment officer of Josie Maran Cosmetics Anna Petrosian David Sultineau, ceo of Kendo Brands Inc. Shay Mitchell Brian Driscoll, ceo Diamond Foods Inc. Victoria Beckham Tracey Sameyah, ceo and Harold Lancer of Lancer Skin Care LLC Kristin Cavallari Tim McMeekan, ceo of Lorac Cosmetics Chelsea Houska Aihui Ong, ceo of EdgiLife Media Inc. Troian Bellisario Michael Katz, owner of Matisse Footwear Nina Agdal Andy Benson, vice president of CytoSport Inc. Vanessa Hudgens Brian Goldner, ceo of Hasbro Inc. Emily Ratajkowski and Ashley Benson Maria Hatzistefanis, ceo of Rodial Limited Denice Moberg Hugh McGuire, ceo of Glanbia Performance Nutrition Inc. James Harrison Ian Danney, owner of Optimum EFX Formulations LLC Scott Disick Jake Munday, co-owner and director of Pearly Whites Australia Lindsay Lohan Ferit Rahvanci, manager of Pinner USA Inc. Kourtney Kardashian Cheryl Bachelder, ceo of Popeyes Louisiana Kitchen Inc. Zendaya and Bella Thorne Jay Piccola, president and GM of Puma North America Sophia Bush Whitney Tingle, ceo of Sakara Life Massy Arias Richelieu Dennis, ceo of Sundial Brands LLC Farrah Abraham Walker Williams, ceo of Teespring Inc. Lisa Rinna Jana Toohey, president of ToGoSpa LLC Troian Bellisario Joshua Koudelka, owner of Understated Leather Akon (Aliaune Damala Badara Thiam) and Jennifer Lopez Alexander Mechetin, ceo of JSC Synergy Group Lucy Hale Kate Voegele, We The Dreamers LLC Vanessa Lachey Brant Cryder, president of Yves Saint Laurent North America

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