10 years ago it was nearly impossible to find out who called with a private number. You would basically have to get a court order in order to find out who called. It would even take days, weeks and 100’s of dollars in expenses just to find out information about the number that showed up as blocked on your phone.
Fast forward to 2017 and there is a service that uses technology that is really clever. The law right now allows anyone to block or hide their real number. But 800 numbers are excluded from the law are are suppose to show up on your phone as unblocked. Technology directs your unanswered blocked call to an 800 number then back to you. It will reach your voicemail, recording the number as it squirts through its servers.