| William R. Helmbrecht | Turfway Park
27-Mar-26,
Run In Gold |
| William R. Lewis, Jr. | Charles Town
05-Jun-26,
Ifthedevildanced |
| William R. McDonald | Mountaineer
26-May-26,
Echo Vision |
| William Renwick | Geraldton
16-Nov-25,
Clever Combat |
| William S. Harris | Remington Park
22-May-26,
Ts Cyber Hunny |
| William S. Meister | Laurel Park
28-Mar-26,
Cashpoint |
| William Smart | Morphettville Parks
24-Aug-13,
Silent Savannah |
| William Souchet | Caen
23-Mar-23,
Jivago De La Cour |
| William Sprague | Taree
28-Feb-10,
In Times Eye |
| William Stinson | |
| William Stinson, Jr. | Churchill Downs
12-Jun-26,
Sunset Harbour |
| William Stites | Penn National
07-Feb-25,
Charge That Dress |
| William Straughn | Charles Town
11-Jan-25,
Adios See Ya |
| William Tharrenos | Gulfstream
06-Apr-26,
Accelerando |
| William Tourangeau | Assiniboia Downs
21-May-25,
Gallant Oak |
| William Turner | Bendigo
17-Dec-17,
Fortuna's Boy |
| William Wain | Armidale
01-Mar-20,
Spatula |
| William Walden | Churchill Downs
22-Jun-26,
Envision |
| William Weeks | Rockhampton
26-Jun-23,
Lingjun Topgun |
| William White Iii | Churchill Downs
11-May-26,
Stormiest |
| William Witherow | Mountaineer
17-Sep-24,
Zero For Conduct |
| Williams Cano | Churchill Downs
01-Jun-26,
Homie |
| Willie J. Kee | Laurel Park
09-May-26,
Rehoboth Avenue |
| Willie Kee | Penn National
18-Jul-24,
Tohonorstelle |
| Willie Kirkland | Fair Grounds
23-Mar-24,
Gloria's Boy |
| Willie Parker | Geraldton
30-Apr-26,
Patchwork |
| Willie Simien Jr | Sam Houston Race Park
30-Apr-23,
Sumpns Up |
| Willoughby Simpson | Gulfstream
01-Jun-26,
Vayesta |
| Wilson | Toodyay
27-Sep-15,
False Lead |
| Wilson C. Langley | Mountaineer
17-Jun-26,
Frozen Four |
| Wilson Langley | Mountaineer
18-Jun-25,
City Humor |
| Winston Lewis | Lone Star Park
09-Nov-25,
Go Zippalitas |
| Wlaimar Suarez | Mountaineer
21-Sep-23,
Dubrovnik |
| Woo Ku | Seoul
18-May-25,
Thunder Lucky |