Most Oscar nominations for best original screenplay

Woody Allen (USA) has received 15 nominations for Best Original Screenplay. His first nomination was for Annie Hall (USA 1977), which he won in addition to Best Actor in a Leading Role and Best Director; his 15th nomination was for Midnight in Paris (USA 2011) in January 2006 - his 21st nomination in total for all categories. 25 nominations/wins:
MIDNIGHT IN PARIS (2011)-- Winner, Writing (Original)
MIDNIGHT IN PARIS (2011)-- Nominee, Directing
MIDNIGHT IN PARIS (2011)-- Nominee, Best Picture
MIDNIGHT IN PARIS (2011)-- Nominee, Art Direction
MATCH POINT (2005) -- Nominee,Writing (Original)
DECONSTRUCTING HARRY (1997) -- Nominee, Writing (Original)
MIGHTY APHRODITE (1995) -- Nominee, Writing (Original)
BULLETS OVER BROADWAY (1994) -- Nominee, Directing
BULLETS OVER BROADWAY (1994) -- Nominee, Writing (Original)
HUSBANDS AND WIVES (1992) -- Nominee, Writing (Original)
ALICE (1990) -- Nominee, Writing (Original)
CRIMES AND MISDEMEANORS (1989) -- Nominee, Directing
CRIMES AND MISDEMEANORS (1989) -- Nominee, Writing (Original)
RADIO DAYS (1987) -- Nominee, Writing (Original)
HANNAH AND HER SISTERS (1986) -- Nominee, Directing
HANNAH AND HER SISTERS (1986) -- Winner, Writing (Original)
THE PURPLE ROSE OF CAIRO (1985) -- Nominee, Writing (Original)
BROADWAY DANNY ROSE (1984) -- Nominee, Directing
BROADWAY DANNY ROSE (1984) -- Nominee, Writing (Original)
MANHATTAN (1979) -- Nominee, Writing (Original)
INTERIORS (1978) -- Nominee, Directing
INTERIORS (1978) -- Nominee, Writing (Original)
ANNIE HALL (1977) -- Nominee, Actor in a Leading Role
ANNIE HALL (1977) -- Winner, Directing
ANNIE HALL (1977) -- Winner, Writing (Original)

See: http://www.scriptpimp.com/show_me/oscars/index.cfm?StartRow=26&show_me=25&search_criteria=null