Geldings in the Kentucky Derby

In 150 runnings, so far, nine geldings —
Vagrant (1876), Apollo (1882), Macbeth II (1888), 

Old Rosebud (1914), Exterminator (1918), 

Paul Jones (1920), Clyde Van Dusen (1929), 

Funny Cide (2003) and Mine That Bird (2009) 

are the only geldings to have won the Kentucky Derby.