My sister recently went on a sales call and when she told them what company she worked for they were upset. They told her that the company she works for is stealing their customers by intercepting and forwarding their phone calls.
Sure enough when my sister dialed their number it was going to her company!
I have looked all over the internet and no luck in finding an answer. How is this possible and how would this company stop this other company from doing this?
It took me a while to understand this question. I believe that the problem is "Dialing the number registered to Company A connects the caller to Company B".
Ultimately, this is an issue that can be resolved with systematic troubleshooting.
1) The caller is making a mistake (dialing the wrong number). Some phone exchange systems may expect particular prefixes or suffixes that require the caller to modify the number they input.
2) The phone provider the caller is using is misdirecting the call somehow (deliberate or accidental). You can rule this out by repeating the call from a different provider (use a difference cell phone company, or a pay phone).
3) Company B does actually own the number being called; the error is in the caller thinking the number belongs to Company A.
I very much doubt that any "call intercept" is being performed here. It's difficult to do unless you have significant access to the telecommunications network - it's the sort of thing that we would expect only government agencies to be capable of doing. Tampering with the phone system is usually illegal in any country, and doing so in this way would immediately lead investigators to their prime suspect.
An interesting question. An alternative variation of scenario 2 from @scuzzy-delta would be that the phone provider that the callee uses is redirecting the call, with the provider that the caller is using being irrelevant. This could be possible as a result of some social engineering of the phone provider. One would imagine that the complainant would then be receiving no calls at all though.
A further and somewhat likely scenario is that the calls are being received by the correct company, and the company is itself forwarding to its competitor. If the complainant has any kind of PBX system, a disgruntled employee may have misconfigured this to dial back out, or it could be a genuine mistake by an incompetent employee. Trivial to do in systems such as Asterisk.
