The fifteen Oscars that went under the hammer at the Nate D. Sanders Auctions collected a total of more than $3 million. Herman Mankiewicz's 1942 Best Screenplay Academy Award for "Citizen Kane," led the auction with a winning bid of more than $588,000. 　　The 1933 Oscar for best picture "Cavalcade," came in second, after selling slightly over $332,000. The 1941 Academy Award for Best Picture, "How Green Was My Valley," also generated a high price, fetching around $274,000. 　　The Academy of Motion Pictures Arts and Sciences forbids Academy Award winners to sell their golden statuettes, but the agreement only dates back to 1950. All 15 Oscars up for sale at the auction house were handed out before that time.