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A similar release of "anonymized" NYC taxi data from 2013 shows that trip information can be pretty revealing.

https://gawker.com/the-public-nyc-taxicab-database-that-acci...

That wasn't anonymized, strictly speaking, it was (badly) hashed/encrypted, and it didn't actually reveal anything, it was pairing the data with photographs of the celebrities (and photos that included the cab license number).

And after all, out of 173 million rides some 5 (five) were "identified".

Fuzzing the locations might be useful if it's allowed but if they have to send the data within 5 seconds fuzzing the time won't do much. It's probably also not that hard to correlate the fuzzed start/end points and the full route which would be harder to fuzz effectively.

As always, your adversary isn't subject to your rules, man. I can defuzz that easily with the time granularity required by the report combined with other information sources - none of which individually break the privacy budget but all of which together can.

Yeah, agreed on time granularity. Without that I think it’d be fine.