Caller ID is for "presentation" only, not billing. Anyone with the appropriate access can set their caller ID to whatever they want. Some VOIP providers don't d

Caller ID is for "presentation" only, not billing. Anyone with the appropriate access can set their caller ID to whatever they want. Some VOIP providers don't do any validation that you "own" the number you are providing. Years ago, when I had an Asterisk PBX set up using a super cheap SIP provider, you could put anything you wanted in for a caller ID. There are legitimate use cases for this. Imagine if you are a company with 1000's of physical locations. You want them all calls to appear that they are coming from the corporate headquarters.