| O B's | Golden Gate Fields, 2024-01-28 |
| O Besos | Churchill Downs, 2024-05-03 |
| O C Rhapsody | Turf Paradise, 2025-02-23 |
| O Captain | Gulfstream, 2025-05-25 |
| O Cigano | Thistledown, 2023-09-28 |
| O DANNY BOY | Warwick Farm, 2010-08-21 |
| O Dirlada | Cagnes-sur-Mer, 2025-01-21 |
| O Dogg | Canterbury Park, 2024-08-12 |
| O Donovan Rossa | Remington Park, 2025-05-04 |
| O Faolains Lass | Wexford, 2023-06-01 |
| O Firefaster | Remington Park, 2025-04-13 |
| O Fortuna | Newcastle, 2025-09-09 |
| O G Beachwear | Wolverhampton, 2023-12-23 |
| O Gangster | Gulfstream, 2023-05-19 |
| O Gre Des Saisons | Toulouse, 2025-05-21 |
| O K Angel | Chukyo, 2025-08-30 |
| O K Baby | Mahoning Valley, 2024-04-12 |
| O K Birdie | Fukushima, 2025-06-28 |
| O K Bonita | Sonoda, 2023-07-26 |
| O K Carmen | Kyoto, 2025-10-12 |
| O K Dragon | Sonoda, 2023-09-06 |
| O K Dyna | Sapporo, 2025-09-07 |
| O K Game On | Finger Lakes, 2024-11-06 |
| O K Grace | Sapporo, 2025-08-17 |
| O K Grit | Tokyo, 2025-10-13 |
| O K Mahina | Fukushima, 2025-07-19 |
| O K Minerva | Kasamatsu, 2025-08-27 |
| O K Passion | Kawasaki, 2024-03-14 |
| O K Pirates | Saga, 2024-03-02 |
| O K Rose | Santa Anita, 2025-10-11 |
| O K Sign | Kasamatsu, 2025-10-07 |
| O K Smarty Pants | Charles Town, 2025-10-16 |
| O K Smile | Tokyo, 2025-10-13 |
| O K Sonic | Kawasaki, 2025-10-13 |
| O K Thunder | Saga, 2025-08-16 |
| O K To Dance | Mountaineer, 2025-07-16 |
| O K Tomboy | Sapporo, 2025-08-30 |
| O Kabukimono | Saga, 2023-12-18 |
| O Mais Grande | San Isidro, 2025-02-22 |
| O Mandy | Del Mar, 2024-07-26 |
| O Meigo | Bordeaux Le Bouscat, 2025-03-05 |
| O Merisi | Cork, 2023-07-29 |
| O Mio Babbino | Killarney, 2023-07-21 |
| O Net Leo | Sonoda, 2025-04-22 |
| O Net Olive | Ohi, 2025-01-15 |
| O P Firecracker | Laurel Park, 2025-10-19 |
| O Patrao | La Teste De Buch, 2024-07-21 |
| O Rei Daddy | Hipodromo Chile, 2025-02-14 |
| O Romeo | Mountaineer, 2025-10-08 |
| O S U Budke | Will Rogers Downs, 2025-04-08 |
| O Seeyalater | Will Rogers Downs, 2025-09-29 |
| O Shaughesey | Mountaineer, 2025-08-12 |
| O She's Warm | Nagoya, 2024-12-18 |
| O Shin Angel | Sonoda, 2025-10-16 |
| O Shin Azuki | Ohi, 2024-10-15 |
| O Shin Bouquet | Urawa, 2025-08-20 |
| O Shin Candy | Sonoda, 2025-09-11 |
| O Shin Clapper | Kochi, 2024-02-07 |
| O Shin Dia | Mizusawa, 2025-06-29 |
| O Shin Es | Chukyo, 2025-08-30 |
| O Shin Half | Kyoto, 2025-10-04 |
| O Shin Leben | Ohi, 2025-03-13 |
| O Shin Million | Kochi, 2025-10-19 |
| O Shin Peach | Urawa, 2025-01-08 |
| O Shin Plus | Funabashi, 2024-02-09 |
| O Shin Rokuzero | Ohi, 2025-06-11 |
| O Shin Scat | Kawasaki, 2025-10-13 |
| O Shugah Mint | Ruidoso Downs, 2024-06-17 |
| O Sole Mio | ParisLongchamp, 2025-09-04 |
| O Sole Mio | Valparaiso Sporting Club, 2023-10-31 |
| O Sole Rika | Funabashi, 2025-06-06 |
| O Sonho Acabou | Amiens, 2023-10-10 |
| O Space O | Greyville, 2025-10-07 |
| O T C Wiz | Penn National, 2024-03-22 |
| O Trasno | Mont De Marsan, 2024-08-01 |
| O V Shine | Mombetsu, 2025-08-05 |
| O Wow | Woodbine, 2024-12-02 |
| O. D.'s Ann Baby | Canterbury Park, 2023-07-03 |
| O' Bon Pardon | Bellewstown, 2025-07-06 |
| O' Dells Star | Lingfield, 2023-11-18 |
| O' Monty Zuma | Yea, 2010-12-18 |
| O' Ole | TRIAL Randwick, 2025-02-13 |
| O' Patrick | Kentucky Downs, 2025-08-31 |
| O' So | Coffs Harbour, 2014-08-06 |
| O' So Hazy | Caulfield, 2020-05-30 |
| O'amelia | TRIAL Coonabarabran, 2021-04-24 |
| O'ashi | TRIAL Grafton, 2024-05-16 |
| O'babe | Canterbury Park, 2025-08-03 |
| O'banion | Emerald Downs, 2024-06-29 |
| O'Boy | |
| O'brien | Monmouth Park, 2024-07-28 |
| O'britzelle | Scone, 2025-10-13 |
| O'caldino | Toowoomba, 2025-08-09 |
| O'CALLAHERN | |
| O'calloghan | Sunshine Coast, 2023-01-22 |
| O'carballo | Dax, 2023-08-07 |
| O'Ceirins Belle | Pukekura Raceway, 2025-08-16 |
| O'ceirins Dream | New Plymouth Raceway, 2024-06-06 |
| O'ceirins Secret | Warrnambool, 2019-02-05 |
| O'Connell | Newcastle, 2025-02-23 |