Simon Toaldo, the managing director, who joined last September, has decided to quit the company, along with the finance director, Ian Robertson, and the comms strategy partner, David Indo. At the same time, Ingram is stepping back from his day-to-day involvement with the company.
An official statement said: "We have carried out an infrastructure commensurate with our original ambitions, and since those ambitions have not been realised, we have decided to scale back the business with immediate effect."
Talks have already started with potential partners to shore up the UK operation.
Ingram admitted: "We set up with a wish to change the market, but we just don't have enough of that sort of business. The market has changed. Being smart and pricey is less attractive to clients than fast and economic. There is a much smaller market for what we're doing than I thought, and I don't play to my own strengths in a small company."
He added that Ingram is "a nice brand-building business with a blue-chip client list, but it needs to make money".
According to the last figures filed at Companies House, Ingram made a loss of £1.58 million in the year ending 2005.
Ingram launched the company in 2003, two years after selling his Tempus Group to WPP, making a personal fortune of £64 million in the process. As well as Ingram London and its sister operations in New York and Hong Kong, Ingram is also the chairman of Woking Football Club.