By Brendan Sasso - 06/25/13 06:43 PM EDT
The agency advised the companies to use text labels and visual cues, such as shading and clear outlines, to distinguish ads.
The FTC said that if a voice interface, such as Siri, is delivering search results, the company must include an audio disclosure for ads that is "of an adequate volume and cadence" for listeners to understand.
The FTC said the disclosure requirements also apply to searches within social networks such as Facebook.
"For example, if a social network were to stream recommended restaurants based on what a particular consumer’s social contacts have enjoyed, it should clearly distinguish as advertising any information feeds included or prioritized based in whole or in part on payments from a third party," the agency explained.
The FTC acknowledged that companies are experimenting with new services for delivering the information that consumers want, but urged the companies to ensure that their disclosure techniques for ads "keep pace with innovations."