Happens all the time. If you look at RR Auctions, John Reznikoff (president of University Archives) is one of their "authenticators", so it is possible that there could have been some odd bidding, etc.
For example, in RR's auction this month, you will see a Gehrig signed letter request from Willie Ritchie, Jr. (I know because I once owned this letter loooong ago) and it was in EAC Gallery's auction just last month and went for BIG money ($3000+ from what I remember), and, you guessed it, Reznikoff is an "authenticator" for EAC as well.
You do the math
