On paper, Alan Smithee has 43 film and television credits, as well as another 43 credits for directing music videos, comic books, games, and other projects. However, Alan—or Allen—Smithee is a sanctioned pseudonym that actual directors were permitted to use when dissatisfied with a project. In support of directors, the Directors Guild of America forbade the use of a phony film or TV credit through 1968.

"Death of a Gunfighter”, which was released in 1969, changed that. The original director, Robert Totten, and the movie’s star, Richard Widmark clashed. Widmark had him replaced with Don Siegel. When the film was done, neither Totten nor Siegel wanted credit. The DGA agreed that the movie did not reflect either director’s work.

The DGA suggested “Al Smith” for a pseudonym, but the film industry already had an Al Smith, so Alan Smithee was chosen as the standard moniker. The DGA also prohibited any director using the name from discussing the matter.

In 1998, “An Alan Smithee Film: Burn Hollywood Burn”, starring Eric Idle of “Monty Python’s Flying Circus” fame, changed things again. The premise: Director Alan Smithee (Idle) wants to distance himself from the film he has made, but the only pseudonym available is “Alan Smithee”, his own name. The movie was a box office and critical failure and Director Arthur Hiller wanted himself distanced from it, so Alan Smithee got the directorial credit.

The name was retired after that.

More Info: en.wikipedia.org