Ingravescentem Ætatem is a motu proprio (document) issued by Pope Paul VI, dated 21 November 1970. It is divided into 8 chapters.
Original text: Ingravescentem aetatem inter et aptitudinem ad quaedam maioris momenti officia, veluti Episcopi dioecesani et parochi, implenda naturalis ratio intercedens a Concilio Oecumenico Vaticano II tractata est in Decreto a verbis Christus Dominus incipiente atque Nosmet ipsi, vota Patrum Concilii ad effectum deducentes, per Apostolicas Litteras Ecclesiae Sanctae, die VI mensis Augusti anno MCMLXVI motu proprio datas, Episcopos et parochos invitavimus, ut munere regendae dioecesis aut paroeciae non ultra expletum septuagesimum quintum annum sponte se abdicarent.
In this motu proprio the pope changed some regulations concerning cardinals participating in a papal conclave. Cardinals who reach the age of 80 lose their right to vote in the conclave. Cardinals do not lose their membership of the Sacred College of Cardinals.
Another element concerned the cardinals membership of Curial Congregations, who automatically lose their membership at 80.
This new regulation meant that during the Papal conclave of October 1978, 25 cardinals became ineligible to vote for the first time in a papal conclave, among them were the cardinals Antonio Caggiano (Cardinal Archbishop of Buenos Aires), Giacomo Lercaro (Cardinal Archbishop of Bologna) and Carlos Carmelo Vasconcellos Motta (Protopriest of the College of Cardinals).
Although Cardinal Walter Kasper turned 80 a few days before the Conclave of 2013, he was not excluded (he was under 80 when the papacy became vacant). Thus, he was the oldest Cardinal Elector in that conclave.
Some Cardinals were did not accept the changes, notably Alfredo Ottaviani and Eugène Tisserant.