Just a reminder that anonymization is much harder than merely removing metadata:

Every time I hear "anonymous data", I think of that time AOL published anonymized search logs (for academic research). The anonymization was negligent, and an NYT reporter de-anonymized and tracked down one of the users with the local & personal info present in the search queries.

https://en.wikipedia.org/wiki/AOL_search_log_release

https://web.archive.org/web/20130404175032/http://www.nytime...