As a sibling comment says, I didn't actually make any privacy statements. However, startpage's help pages claim not to pass on IP addresses, useragents, cookie

As a sibling comment says, I didn't actually make any privacy statements. However, startpage's help pages claim not to pass on IP addresses, useragents, cookies, or other identifying information. This claimed-independent report says so too: https://www.european-privacy-seal.eu/awarded-seals/de-110022/ https://www.european-privacy-seal.eu/awarded-seals/de-110022... — verifying such statements is hard; believe what you will. I agree, it seems clicking on the Google ads (rather than search results) does put a request via google.com/aclk. Privacy conscious users could block ads to avoid such mistakes. Of course startpage must send some data to google: the search terms are needed to get the search results themselves (as well as for selecting the ads). That could be a privacy leak, for example if simultaneously searching for a name and a sensitive topic. It doesn't seem nearly as bad as tying the search terms to a unique identifier across searches however.