We follow the industry standard of marking all sponsored links with the “nofollow” attribute, which tells search engines not to take these links into account when they are ranking webpages.

As an example, Google’s guidelines state:

Paid links: A site's ranking in Google search results is partly based on analysis of those sites that link to it. In order to prevent paid links from influencing search results and negatively impacting users, we urge webmasters use nofollow on such links. Search engine guidelines require machine-readable disclosure of paid links in the same way that consumers online and offline appreciate disclosure of paid relationships (for example, a full-page newspaper ad may be headed by the word "Advertisement").