Here's an article from eSports Collector's Digest:
BOGUS ALI AUTOGRAPHS ON RISE, BOXER SAYS
By Rocky Landsverk
Muhammad Ali has signed perhaps a million autographs in his lifetime, and it has not been enough to meet demand. Ali and Harlan Werner, his long-time agent, have taken to the offensive to alert fans that there's a serious problem with fake autographs of the sports legend.
"I'm not concerned about the value of my autograph; I'm concerned that my fans who are buying it are getting the real thing," Ali said, responding via e-mail in an exclusive interview. "My team has been with me for several years and is doing the best they can to keep up with the forgers."
Werner stresses that he's not on an "everything is fake but what we sell" rampage, but said Ali wants fans to employ some common sense, because many of the offers available just can't be valid.
"It's not physically possible for Muhammad to sign 30,000-50,000 autographs a year, and that is an approximation of the number of signatures being pumped into the marketplace worldwide," Werner said. "He wants the message to be out that fans and collectors should use common sense, know who they're buying from, and be comfortable with who they're buying from."
And when he says worldwide, he means it. "This problem is worse in Australia, worse in Japan, worse in England than it is in the United States," Werner said. "The noose is tightening (in the United States) and this stuff is being shipped abroad."
Ali's physical condition has worsened his autograph, something the forgers often utilize to their advantage. It's hard to authenticate Ali's signature, and not that hard to call a forgery "just one of Muhammad's bad days." Werner, however, said forgeries are still apparent to those who know Ali's autograph.
"There are days when he can sign very large signatures, and there are days when you get very small signatures," Werner said. "However, when he is sitting down and signing autographs, the characters are always similar and consistent. The inconsistency is in the size, and the signatures that are signed out in public are usually rushed and chances are you're going to get a signature that's less legible. Those less-legible signatures are more commonly counterfeited, and those signatures signed 'Muhammad Ali aka Cassius Clay' or just 'Cassius Clay,' those fake signatures are being pumped out in large numbers."
For more details, see the complete story in the June 11 issue of SCD.