We never used this data, other than showing favicons.
In fact, we didn't (and don't in general) collect any user-level data in the first place, per our strict privacy policy: https://duckduckgo.com/privacy
In this case, the way it works is you hit our favicon service and it returns the favicon, not using any PII in the process, and our web servers are configured not to log any PII. In other words, our system is technically designed and we are legally bound by our privacy policy to not use this data for anything other than showing favicons.
In fact, we didn't (and don't in general) collect any user-level data in the first place, per our strict privacy policy: https://duckduckgo.com/privacy
In this case, the way it works is you hit our favicon service and it returns the favicon, not using any PII in the process, and our web servers are configured not to log any PII. In other words, our system is technically designed and we are legally bound by our privacy policy to not use this data for anything other than showing favicons.