Google has published best practices for bloggers who receive free products from companies. Adhering to these guidelines is required under Google's Webmaster Guidelines, and non-compliance may lead to a site being removed from the Google index or otherwise being affected by an algorithmic or manual spam action.
The best practice guidelines include a requirement of using the "nofollow" tag where appropriate (specifically in the case of links that pass PageRank in exchange for goods or services); a requirement to disclose the sponsored relationship; and guidelines regarding content quality.
These guidelines demonstrate the increasing regulatory scrutiny concerning native advertising and sponsored online endorsement/influence. As reported in detail below, this issue has been declared as a regulatory priority by regulators, such as the FTC, and we expect to see increased enforcement and industry guidance in this field.