Now, at a time when the sports-memorabilia market is surging, PSA/DNA and JSA are both saviors — to individuals who won’t spend thousands on an item without third-party verification of its authenticity — and killjoys — to the scammers and sharks who had, for years, feasted on those individuals. They’re the entities that collectors, auction houses and even investors seek out to determine whether an autograph, card, bat, ball or jersey is authentic. Their role is one part detective and one part card-store geek. They are the Coke and Pepsi of the authentication business.

And make no mistake: It is a big-time business, as opposed to a mere offshoot of a hobby. Together, PSA/DNA and JSA validate the genuineness of hundreds of thousands of items per year, charging anywhere between $25 and $500 per item authenticated; PSA/DNA ­parent company Collectors Universe, which also has a coin ­authentication-and-grading arm, is publicly traded on the NASDAQ exchange. “We’re seeing pieces that sold for $50,000 in 2000 selling for hundreds of thousands of dollars today,” says Chris Ivy, director of sports auctions at Heritage Auctions, which exceeded $30 million in auctions and direct sales for the first time in 2013. “Our market is ­immune to the kind of [financial] crash we saw in 2007-2008 because it’s impossible to manipulate. There are perhaps five Babe Ruth jerseys in existence. Nobody is making more. Nobody is hedging against them.”

At the same time, the business remains strikingly personal for many who work within it, just as it does for buyers and ­sellers emotionally bonded to the items they covet or own. It’s also a lot of fun: PSA/DNA president Joe Orlando relishes the tale of an Elvis Presley autograph given the thumbs-down by PSA/DNA because the book upon which it was inscribed was published 15 years after his death. Spence, for his part, marvels about the interest in the prosthetic leg that once belonged to former Chicago White Sox owner Bill Veeck. “He was about to get a new one, so he signed the old one and gave it to a bar.”

“This is the rare business where it’s not just about the money,” says Orlando. Indeed, there’s a degree of emotional attachment, which makes the job of the authenticators even more challenging, as they often find themselves in a position where they must deliver bad news.

There’s also the thorny issue of control, which rears its head during interactions with longtime collectors used to being the final authority on their possessions and purchases. Alan “Mr. Mint” Rosen, a legendary baseball-card dealer who was featured in the April 1, 2013, issue of this magazine, stresses that third-party card graders and authenticators “are good for our business.” But he chafes at both the definitive nature of their verdicts and their pricing. “I bought these two 1954 Bowman cards, and [the authenticator] told me they were both 6s [on a 1-to-10 scale] because there were print dots. I looked at the cards with a magnifying glass and couldn’t see a thing. I paid $250 for this? Ridiculous.”