The site’s owner, the Royal Agricultural Society of England (RASE), was financially hit last year when the successor to the Royal Show — the Royal Festival of the Horse — made heavy losses.
Now property fund managers LaSalle Investment Management will pour £20m into the site by the end of 2012 and up to £50m by 2020.
Mr Bull said that the park had been “hampered by lack of money” in the past.
LaSalle, which runs four science business parks, has taken a 150-year lease on the site, but equestrian competitions there will continue to be run by Stoneleigh Park Ltd.
Insiders say the Royal Festival of the Horse is not on this year’s calendar.
British Equestrian Federation (BEF) chief executive Andrew Finding believes this deal may allow plans for a National Equestrian Institute (NEI) at Stoneleigh to progress.
And British Dressage’s (BD) chief executive Amanda Bond also welcomed the deal.
“Anything that guarantees the long-term viability of Stoneleigh Park is good, so long as the development of the site continues to embrace the specific needs of our industry,” she said.
The dark cloud casting a shadow on potential development is HS2, the high-speed train link that may cut Stoneleigh in two.
British Eventing’s Mike Etherington-Smith believes the park’s future remains uncertain.
“The lease for the offices which we, the BEF, BD and British Showjumping currently occupy, expires in 2017.
“We’ve been discussing whether we seek to relocate on the showground or move offsite.
What we want is to stay together,” he added.
RASE and LaSalle will continue to take part in HS2 consultations to prevent the railtrack going straight through the park.
This news story was first published in the current issue of Horse & Hound (13 January, 2011)