"Citizen Kane": No matter what anybody says, "It's Terrific!"
Edward Copeland had a bunch of questions about anomalies in Oscar history and technicalities in the (ever-changing) rules. So, he went straight to the source, the staff of the Academy's Margaret Herrick Library, and sent them an e-mail with his queries. Now he's got the answers, which you can read at Edward Copeland on Film.
Question No. 4.: For years I heard the statistic that Orson Welles was the first person to be nominated as producer, director, actor and writer for a single film for "Citizen Kane" until Warren Beatty repeated the feat twice for "Heaven Can Wait" and "Reds." Later, the Welles stat seemed to be revised under the argument that in 1941, the studio head would have won the Oscar if "Citizen Kane" had taken best picture. Should Welles be considered as having had four nominations for Kane or not?
Answer: From a strictly statistical standpoint, no. The rules were not the same then as now, so technically, as that statistic is stated, you can only apply it to films from the 1951 (24th) Awards on, when the nominees for Best Picture become the individually named producers rather than the production companies. The nominee for Outstanding Motion Picture for "Citizen Kane" was Orson Welles' company Mercury. So if you want to consider that being in the "spirit" of the statistic, feel free. In which case, you might also want to give consideration to Charlie Chaplin and his Honorary Award for "The Circus," given how the citation is worded. But again, from a strict statistical standpoint, neither of these two meet the Warren Beatty statistic of 4 competitive nominations for the same film in the stated categories.