Graeme and Susan Shaw established Matakauri Lodge, near Queenstown, and sold it in 2001 for $7 million with a condition stating the couple, now based in Sydney, would get seven days' full board a year at no cost.
They thought it was an entitlement for life.
But the lodge has changed hands since, and when American billionaire Julian Robertson bought it for $12 million in 2009, the clause was not part of the sale.
The Shaws took High Court action against law firm Macalister Todd Phillips, who acted for them in 2001, claiming negligence - but in an August 19 judgement Associate Judge Rob Osborne dismissed the claims because they were outside a six-year statutory limitation period.
Mactodd partner Richard Cunliffe said it was not unusual for law firms to be sued, which was why they had professional indemnity insurance.
''What is a little unusual is the publicity. Often, these things don't hit the papers.
''But we're quite comfortable that we haven't done anything wrong and the Shaws have left it far too late to raise the issues.''
When contacted by the Otago Daily Times, Graeme Shaw said he did not want to comment before consulting his lawyer.
Matakauri Lodge has had some high-profile visitors this year: in April, the Duke and Duchess of Cambridge had a night there without baby Prince George, and, more recently, alleged internet pirate and politician Kim Dotcom stayed there with his family.
Rooms cost up to $12,750 a night.
