[philippclassen]

(Disclaimer: I work at Cliqz)

Just saw this one. It is an old comment, but let me try to answer as I find the question interesting.

The post on Human Web (https://0x65.dev/blog/2019-12-03/human-web-collecting-data-i...) has a brief section regarding differential privacy. Maybe check that one out first.

My take on it: although we do see value in differential privacy, we do not believe it fits well in our particular case. The critical moment is to decide what data should be sent by the client. Once data it is out, it is out. It is not possible to apply anonymization once it is on the server. If someone knows how it can be done safely, I would be highly interested.

We consider our chosen approach - breaking record linkage before sending - safer for our use-case and simpler. Do not underestimate the simplicity argument. Differential privacy is a powerful technique, but it is also very complex; there are lots of pitfalls and it is crucial to make good choices for the parameters.

Would be a good topic for another blog post. ;-)