The National Advertising Division (NAD) of the Council of Better Business Bureaus says that social-media testimonials must include Federal Trade Commission (FTC) disclosures. Nutrisystem, Inc. re-pinned several weight-loss success stories to its company Pinterest page. The pictures linked back to the Nutrisystem website. The NAD determined that, absent a disclosure, the testimonials were deceptive advertisements.

FTC disclosures are laid out in the Commission’s Guides Concerning the Use of Endorsements and Testimonials in Advertising. Disclosures must clearly and conspicuously state typical results that consumers should expect in similar circumstances, and any material connections between the endorser and advertiser–for example, is the testimony from an employee or a paid source–must be revealed.

Social media presents unique challenges for disclosure. Most messages are short, as with Twitter and Facebook, or primarily graphic in the case of Pinterest. Nutrisystem provided a disclosure on its website, which users were linked to, but that wasn’t enough. The company has since added a “results not typical” disclosure to each pin. But it’s not clear what Nutrisystem would have to do to supplement, say, a testimonial re-tweet, where space is strictly limited, or how aggressively the NAD and FTC will monitor disclosure in the case of such re-tweets.