Gallery faces another forgery complaint.

Byline: Patricia Cohen

NEW YORK -- The art forger Ken Perenyi remembers Anthony Masaccio as a practiced partner in the sale of fake paintings, a man with movie-star looks and the nickname Tony Cha Cha who mingled with models and artists in the back room of Andy Warhol's hangout Max's Kansas City during the 1970s.

In a memoir published last year, Perenyi describes how he painstakingly created fakes that Masaccio hawked to gallery owners out of a Saks shopping bag.

Now Masaccio has surfaced as "a known purveyor in forged art'' in another document -- a newly amended complaint against Knoedler & Co., a gallery that is at the center of an $80...