[Someone]

> Sending the data back to Apple could be more significant. But I guess that’s only of the AirTag is “lost”

To do that, your phone has to know which AirTags are lost.

A solution might be that Apple periodically sends a list of lost AirTags to phones (possibly as a bloom filter or other inexact, but compact, structure), but I’m not convinced it does. Maybe, it bets on AirTags being rare enough (who’s going to buy tens of them? I wouldn’t, as the idea of having to replace those batteries would put me of buying many) for this not to be a problem.