22 CFR § 123.21 - Duration, renewal, and disposition of licenses.
(a) A license is valid for four years. The license expires when the total value or quantity authorized has been shipped or when the date of expiration has been reached, whichever occurs first. Defense articles to be shipped thereafter require a new application and license. The new application should refer to the expired license. It should not include references to any defense articles other than those of the unshipped balance of the expired license.
(b) Unused, expired, suspended, or revoked licenses must be handled in accordance with § 123.22(c) of this subchapter.