 Until 1982, the enforceability of due-on-sale provisions was basically a matter of state, not federal, law.Many states had adopted laws that permitted existing loans to be assumed by buyers whether or not the lender was willing to agree.The logic behind these laws was generally that a lender should be permitted to call a loan due when the property securing the loan is sold only if the lender could demonstrate that the sale and transfer of the property reduced the lender's security or increased the risk that the loan would go into default.