§1. An ecclesiastical office is lost by the lapse of a predetermined time, by reaching the age determined by law, by resignation, by transfer, by removal, and by privation.
§2. An ecclesiastical office is not lost by the expiration in any way of the authority of the one who conferred it unless the law provides otherwise.
§3. Loss of an office which has taken effect is to be made known as soon as possible to all those who have some right over the provision of the office.
Source: Code of Canon Law (Vatican.va)