On June 25, 2013, the Federal Trade Commission's Consumer Protection staff sent letters to the major search engines on the need to distinguish between advertisements and search results: * Sample Letter to General Purpose Search Engines * Sample Letter to Specialized Search Engines The updated guidance has been sent to the general-purpose search engines AOL, Ask.com, Bing, Blekko, DuckDuckGo, Google, and Yahoo!, as well as 17 of the most heavily trafficked search engines that specialize in the areas of shopping, travel, and local business, and that display advertisements to consumers.