| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| Spectator | bay | c | 1749 | Crab | Partner mare | Thoroughbred | Great Britain | |
| Spectre | bay | c | 1835 | Thoroughbred | Great Britain | |||
| Spectrum | bay | c | 1992 | Rainbow Quest | River Dancer | Thoroughbred | Ireland | |
| Spectrum | chestnut | c | 1948 | Nasrullah | Thoroughbred | Great Britain | ||
| 3372-5 Spectrum Role | bay | f | 2002 | Spectrum | Starring Role | Thoroughbred | Ireland | |
| Speculation | f | 1885 | Livingstone | Springflower | Thoroughbred | |||
| Speculator | bay | c | 1795 | Dragon | Thoroughbred | Great Britain | ||
| Speculator mare | chestnut | f | 1813 | Speculator | Dare Devil mare | Thoroughbred | USA | |
| Speculum | c | 1865 | Vedette | Thoroughbred | ||||
| Speed | bay | f | 1885 | Spurs | Thoroughbred | Austria |