[fwlr]

I’ll admit I simply assumed there was adequate encryption to avoid leaking location data in undesirable ways and didn’t think to investigate how they were doing it (generally an unsafe assumption - although, credit is due to Apple, slightly less unsafe in their case!).

The system being “my iPhone encrypts its location with the lost device’s public key, so only the holder of the corresponding private key (i.e. the owner of the lost device) can see that location” is actually sublime, though. That’s the minimal amount of information and yet it still achieves the highest level of privacy, right? Only the location data from the adult, only the public key from the lost child, combined in such a way that cryptographically guarantees only the parent can read the location data. No Apple IDs or serial numbers or any other identifying information even included, so it’s robust even against broken encryption. Very cool.