Land agent Strutt & Parker is in the middle of a £100m litigation battle launched by the Earl of Malmesbury earlier this month.
The case stems from a lease negotiated in 1995 by the firm, advising the Earl to rent a 12-acre site next to Bournemouth International Airport for car parking.
This was granted to Manchester Airports Group, which took over the site and expanded the airport in 2000, on a 25-year basis at a rent of £9000/year.
The Earl’s negligence claim is based on the difference between that rent and a potential income of £4m a year.
It is believed that, if successful, the High Court case would be the biggest in surveying history.
Strutt & Parker denies liability. Court papers show it will defend its actions on the basis that it was acting for the long term future of the estate.
A spokesman for the firm said it had a “substantial” amount of professional indemnity insurance, but would neither confirm nor deny if this ran to £100m.
The case continues.