Comment by Y_Y

https://investors.23andme.com/news-releases/news-release-det...

This is complicated. The don't just zip up all the customer data and send it over, at least they say that they run aggregated queries for GSK and just tell them the answer. But then they say that the data is "anonymized" before this, which seems unnecessary and impossible.

Imho it's very difficult to anonymize any data, and especially something like DNA. Without an external audit amd some mathematical guarantee (e.g. differntial privacy) I work on the assumption that they do the bare minimum to pass legal muster but anyone who made the effort could confidently associate the data with real people after the fact.