Andrew Greene is flipping angry about his onscreen alter ego, Nicky "Rugrat" Koskoff, who is played by P.J. Byrne. "Rugrat" is a nod to Greene's nickname "Wigwam," which refers to Greene's hairpiece, and is the butt of several jokes. This and other details make it clear, according to the suit, that Koskoff is based on Greene.
Of course, this $25M defamation lawsuit and injunction against Paramount isn't just about Greene's toupé, although that seems to be a particularly touchy subject. He's also mad that his character is shown participating in some of the lupine shenanigans of Belfort and crew.
According to The Wrap, the complaint reads, "In multiple scenes in the movie, 'Rugrat's' use of a toupee is accentuated and mocked in an egregiously offensive manner... The motion picture introduces 'Rugrat' by referencing his 'piece of sh*t hairpiece.' In another scene, investigators ask whether his hair is real. Characters are also seen attempting to grab the toupee in a scene." Additionally, "The motion picture contains various scenes wherein Mr. Greene's character is portrayed as a criminal, drug user, degenerate, depraved, and/or devoid of any morality or ethics."
Well, sure, Greene was never "interviewed, questioned, charged, imprisoned, or even arrested for the illicit and despicable behavior shown in the motion picture," but he was apparently pretty cool with Belfort's accounts of what went on behind closed doors (and/or on yachts, offices, etc.) in his book. Then again, Paramount is a much tastier target for a lawsuit than the former fraudster.