Phone number always belongs/registered to someone?
Alas, last time I checked numbers were something that was announced in-band, so it could be trivially faked by the caller. But I'm not sure if that's still true.
alt Hacker News
Alas, last time I checked numbers were something that was announced in-band, so it could be trivially faked by the caller. But I'm not sure if that's still true.