The act of making something obvious and clear. Disclosing (divulging or explaining), the purpose and interests of an influencer in his/her published posts.
By disclosing the purpose and relationship of a post, influencers are letting their audience know more about the information they will be reviewing in exchange of money or gifts.
The FTC (Federal Trade Commission) works to stop deceptive ads, and its Endorsement Guides explain in details about how advertisers and endorsers can stay on the right side of the law.
FTC disclosures guidelines