http://veriseal.org/about/
If you really want to know, these guys can tell you. They former SEALs that have a data base of every person that has ever completed BUD/s. The website looks a little different than it did, but it seems as if they will still verify someone as the real deal.
I used to go there every month or so to read the cases of guys they had outed. Everything from 20 year old SEAL Commanders, to guys that were a little more subtle. You would be amazed at the amount of well placed people that had actually accomplished something in life that added t SEAL to their resume.
Reads like a conspiracy theory site.