Prove It was out of the mare Time To Khal, who was sired by Khaled, a multiple stakes winner in England for the Aga Khan III who was purchased by Ellsworth and brought to stand at his Chino, California, stud ranch.
Prove It had a highly successful racing career that included wins in the prestigious Santa Anita Handicap (1961) and Hollywood Gold Cup (1962).
[2][3] He also set an Arlington Park track record in the 1962 Benjamin F. Lindheimer Handicap.
Through daughter Proof Requested, he was the damsire of 1983 Preakness Stakes winner Deputed Testamony.
Prove It's death date is uncertain as he is reported for have died in 1982, but his last offspring, Ladies Quote, was foaled in 1987.