Greenall Guerriero Racing acts as the manager and training operation behind a range of separate partnerships, syndicates and racing clubs. It is not one single closed syndicate: each Horsebox opportunity should have its own share structure, costs, duration and ownership agreement, making clear exactly what members are entitled to. The official ownership offering spans outright ownership, joint ownership, leasing, syndicates and racing clubs.

Oliver Greenall and Josh Guerriero are both former successful amateur jockeys who later developed their careers within leading racing yards. Oliver gained experience with Michael Easterby and Sir Mark Prescott, while Josh worked for Philip Hobbs and Victor Dartnall before spending three years as assistant trainer to Dan Skelton. Josh subsequently joined Oliver at Stockton Hall, and the pair became joint trainers in 2022.

Their partnership is deliberately structured around the different demands of modern training and shared ownership. Oliver focuses particularly on owners, communication and racing, while Josh and the wider team concentrate on the daily training and placement of the horses. The yard states that approximately 90% of its horses are in joint ownership, making syndicates and owner communication central to the operation rather than an occasional addition.

Stockton Hall offers a self-contained National Hunt training environment surrounded by farmland, woods and streams. Facilities include a deep-sand loop, an uphill all-weather gallop, a high-sided jumping lane, an all-weather schooling strip, loose schools, three horse walkers, more than 100 acres of turnout, solariums and vibraplates.