Reopening consent order

Walkden v Walkden [2009] EWCA Civ 627 CA 25 June

Under a deed of separation the wife was to receive 5% of the value of the husband’s shareholding in a private company in the event of a future sale. At her request she received an immediate lump sum instead of that future percentage. The agreement was embodied in a consent order expressed to be in full and final settlement of all claims. Three months later, the company was sold for considerably more than the husband’s original estimate of its value. Was this an unforeseen and unforeseeable supervening event sufficient to satisfy the test in Barder v Caluori [1988] AC 20 HL? In the alternative had the parties and the court proceeded on a mistaken premise, namely that the husband’s shares were worth a sum which, although not certain, was on the husband’s evaluation about 10% of what they had been worth?