When Matt Federgreen was approached by a man with a dozen items autographed by baseball great Roberte Clemente, the hair on the back of his neck stood up.

The collection included a check signed by the Pittsburgh Pirates All Star, but the seller was not aware of the value of his items and acted suspiciously.

"He claimed that the items belonged to his father who had passed away, but I assumed that the signatures were phony," said Federgreen, owner of Beverly Hills Baseball Card Shop.

It turned out that they were authentic after all but stolen.

About a week later, Federgreen received a call from someone looking for his collection of autographed Roberto Clemente memorabilia that was taken from a storage locker.

Welcome to world of sports memorabilia, where a significant growth in forgeries and the trade in stolen items has dampened enthusiasm for what had been a rapidly growing pastime among rabid fans and high-brow collectors alike.

While forgeries and stolen goods are a problem with museum objects, antiquities and other collectibles, they have posed a special problem for sports memorabilia with its broad appeal and availability to millions of sports fans.

The problem is so extensive that the Federal Bureau of Investigation has been conducting an investigation of sports memorabilia fraud since 1997.

The investigation, dubbed Operation Bullpen, at one point involved the establishment of a fake company that traded in sports memorabilia; it helped identify forgers and dealers who were distributing fake items. The first phase of the probe led to 26 convictions in Southern California while the second phase resulted in an additional 40 arrests.

"Muhammad Ali is probably the most forged signature in the world," said FBI special agent Tim Fitzsimmons, the lead investigator for Operation Bullpen, which is being led by the bureau's San Diego field office.

Technological solutions
Law enforcement officials aren't the only ones attempting to combat the problem. With millions of dollars at stake, collectors, legitimate dealers and even the athletes themselves are taking steps to quell fears among collectors.

Some athletes, for example, are turning to marketing firms and other specialists that authenticate memorabilia bearing the athletes' signatures before they hit the market. Athletes also rely on the firms to track down and destroy forgeries.

"Some people can make millions of dollars a year off of licensing and their image," said Harlan Werner, founder of L.A.-based Sports Placement Service Inc., a company that represents retired athletes including Sandy Koufax, Joe Namath, Jim Brown and the Ali brand. The company recently announced the addition of Mike Tyson as a client.

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