The DuckDuckGo privacy policy states: "At some other search engines (including us), you can also use an encrypted version (HTTPS), which as a byproduct doesn't usually send your search terms to sites. However, it is slower to connect to these versions and if you click on a site that also uses HTTPS then your search is sent. Nevertheless, the encrypted version does protect your search from being leaked onto the computers it travels on between you and us."