Mark Irwin Forstater (born 1943) is a film producer, writer, and audio producer, notable for producing the film Monty Python and the Holy Grail and then in 2012 suing the five living members of Monty Python over a dispute regarding royalties from merchandising income, including the Spamalot musical, which was "lovingly ripped off from" the Holy Grail movie. He is a graduate of London Film School.