These guys will not stop. They have a bank of phones and I keep getting calls from 480-320-26xx. Today it was Dave Hoskins, from enTrust,  wanting to set up an appointment with "regional sales manager" Mark Pollack to review my Visa/MasterCard merchant account. He called me by name and said this was about my [business name] account. I gently asked enough information to get names and return number (same as caller ID). I asked him who I should be calling at Visa and MasterCard to report fraud because I do not have a merchant account. With no pause at all he asked if did not accept V/MC. I repeated I had no merchant account. He said, so you do not accept charge cards. I said I do not. He said, my name must have gotten onto the wrong list!!  Anyone who has a contract with the federal government has to be listed with some agency called (DOD)ORCA/CCR. These listings are public record. Companies. such as Entrust, harvest the listings and make the calls. I suspect that Entrust is a merchant servicer, one of the middlemen in the charge card business who takes a monthly subscription fee, a per-charge fee and a percentage of the ticket charges. What a waste of time.
They have a page on LinkedIn, http://www.linkedin.com/company/entrust-merchant-services, and a "blank" webpage: http://www.entrustmerchant.com/.

LIke Chicago Ed said: These guys will not stop. They have a bank of phones and I keep getting calls from 480-320-26xx.  I have asked repeatedly to have them remove my name and number from their call list, and yet they continue to harrass.

My phone has the ability to block unwanted calls, but, unfortunately, I get so many calls from this same area, all numbers starting with 480-320-26xx so they would fill the blocked calls list very quickly. For now, I just make a point of not answering those numbers. Just these past six weeks, I have received calls from 408-331-2622, 480-320-2631, 480-320-2638, 480-320-2660, 480-320-2676, 480-320-2679.

I would not be surprised if all those calls come from the same outfit because they all show "UNKNOWN" in the caller ID.

They dont stop and get very pushy.... DONT GIVE ANYTHING AWAY... lady calls me like twice a day.

Called me today for what seems like the 1000th time.  Asked for a supervisor.  Supervisor told me that they don't use a list, that they call off of a review so the only way to stop calls would be to close my merchant account review thus agreeing to continue paying the 40 to 50% more for accepting credit cards.  I said ok, go ahead and close the review.  He then hung up on me.  I'm going to try putting in a call to their state's Attorney General to see if they can do anything to help.