A.P. Indy (March 31, 1989 – February 21, 2020) was an American Thoroughbred racehorse who won the Belmont Stakes and Breeders' Cup Classic on his way to American Horse of the Year honors in 1992. His time in the Belmont Stakes tied Easy Goer for the second-fastest running in the history of the race, behind his damsire Secretariat.
A.P. Indy subsequently became a "breed-shaping sire", leading the North American sire list twice and establishing a sire line that has produced multiple American Classic winners. A.P Indy lived most of his life at Lane's End Farm, where he was born and raised, and stood his entire stud career. For many years, he was the oldest living winner of the Breeders' Cup Classic, the oldest living winner of the Belmont Stakes, and the oldest living winner of a Triple Crown race.
A.P. Indy is part of the only three-generation sequence of Belmont Stakes winners in American racing history. He is by 1977 winner Seattle Slew and is the sire of 2007 winner Rags to Riches.
He was inducted into the Hall of Fame in 2000. He has been called "the fantasy of every Thoroughbred industry participant, from sale-topper yearling, to champion runner, to game-changing stallion to sire of sires." Bill Farish, son of Lane's End founder William Farish, said, "Words really can't put into perspective what he's meant to us. How many sale toppers are yearlings that end up being that good where they are Horse of the Year and then go on and be two-time champion sire and then have the long term influence that he has had and will continue to have? It's pretty amazing."
A.P. Indy lived to age 30, an advanced age for a horse. From June 2017 until his death, he had been the oldest living winner of the Belmont Stakes and the oldest living Classic winner overall. He was also the oldest living winner of the Breeders' Cup Classic. He died on February 21, 2020 due to the infirmities of old age. (His Grandson "Honor A.P. won the Santa Anita Derby on June 6, 2020)