DuckDuckGo has made its name on protecting user privacy and heavily emphasized that in its marketing
So it was unsettling when security researcher Zach Edwards discovered that DuckDuckGo's browser does not block all advertising tracking requests from Microsoft on non-Microsoft sites. His example was Facebook Workplace sending data to Bing and LinkedIn domains.
Browser Not Search Engine
We're talking about the browser, not the search engine.
DuckDuck Go's search engine promotes itself as completely anonymous. DuckDuckGo syndicates search results from Microsoft and works with Microsoft to include ads that are contextual, based on the search terms you type, but not associated with a profile of you.
But DuckDuckGo also makes a browser for Android and iOS and in beta for the Mac with Windows coming soon. It does not promote the browser as anonymous. Instead it promotes the browser as blocking most third-party trackers. And it goes above and beyond other browsers. It not only block third-party cookies and attempts at "fingerprinting" but also proactively stops third-party ad scripts from loading using a process it calls Tracker Radar to identify these attempts.
And one of those scripts from Microsoft is what Edwards found was not blocked from loading by DuckDuckGo's browser. So why the exception?
Why Treat Microsoft Differently?
DuckDuckGo founder Gabriel Weinberg posted on Twitter that its search syndication agreement with Microsoft prevents it from blocking Microsoft scripts on third-party sites from making ad requests.
So why didn't DuckDuckGo say anything before? Weinberg told TechCrunch “Our syndication contract has broad confidentiality requirements, and the specific requirement documents themselves are additionally explicitly marked confidential.”
Weinberg told Bleeping Computer that DuckDuckGo is working to get the Microsoft agreement changed.
There is also concern that this was not disclosed on its App Store descriptions which are supposed to disclose all privacy implications. Weinberg said on Hacker News “We will work diligently today to find a way to say something in our app store descriptions in terms of a better disclosure — will likely have something up by the end of the day.”