In Simkin v. Blank, 19 NY3d 46, 968 N.E.2d 459, 945 N.Y.S.2d 222 [2012], the husband alleged that he and his wife were mutually mistaken about the value of an investment account as it had never actually existed due to Bernard Madoff's Ponzi scheme.

First, the Court observed that "a claim predicated on mutual mistake must be pleaded with the requisite particularity necessitated under CPLR 3016 (b) . . . and that the mutual mistake must exist at the time the contract is entered into and must be substantial," and that any court-ordered relief of reformation is reserved only for "exceptional situations." (Id. at 52).

The Court, moreover, analogized the circumstances with a dispute over marital assets that unexpectedly gained or lost value after the dissolution of the marriage. (Id. at 55).