The rule of the mutual mistake doctrine is that when (1) both parties enter a contract under a mistaken assumption that is (2) basic to the contract, (3) the contract is voidable by the party adversely affected by the mistake, unless (4) that party ought to bear risk of the mistake. When ought a party bear the risk of the mistake? Here is the rule: a party bears the risk of the mistake if (1) the contract assigns the risk to that party; or (2) the party was aware at the time of contracting that he or she had only limited knowledge of the facts relevant to assessing the risk of the mistake and decided to enter the contract anyway; or (3) it is reasonable, in the circumstances for the party to bear the risk of the mistake.