CathInfo.com

"'According to Bellarmine,' explains Don Curzio Nitoglia, '(De Romano Pontifice lib. II. Cap. 30, p. 420), since notorious and public manifest heretics lose jurisdiction ipso facto, granted but not conceded that the pope can fall into heresy, in the eventual case of manifest heresy, he would immediately lose the papal authority. This is the interpretation of the Bellarminian position given by the Jesuit Fathers Franz Xavier Wernz and Pedro Vidal. (Jus Canonicuм), Rome, Gregorian, 1943, vol. II, p. 517).' Then Don Curzio points out that the same interpretation is given by other eminent authorities as well: '(cfr. also L. Billot, Tractatus de Ecclesia Christi, Prato, Giachetti, 1909, tomo II, p. 617; J. Salaverri, De Ecclesia Christi, Madrid, BAC, 1958, p. 879, n. 1047).'

"Against this unanimous interpretation of commentators on Bellarmine made by eminent theologians and canonists who have expounded on the Five Opinions in recent centuries, Salza and Siscoe most stupidly declare:

"'Bellarmine and Suarez (two Jesuits) disagree with the opinion of Cajetan and John of St. Thomas (the Dominicans). As we explain in great detail in our book, Bellarmine and Suarez teach that the Pope will lose his office, ipso facto, once he is judged by the Church to be a heretic, without the additional juridical act of vitandus declaration.'

"And then they explain what (according to them) is the 'erroneous interpretation of Bellarmine' which they characterize as the 'sedevacantist interpretation of Bellarmine', which, (they say), Fr. Kramer has swallowed 'hook, line and sinker':

"'Where the Sedevacantists have erred is by interpreting the ipso facto loss of office to be similar to an 'ipso facto' latae sententiæ excommunication, which occurs automatically (or ipso facto), when one commits an offense that carries the penalty, without requiring an antecedent judgment by the Church. But this is not at all what Bellarmine and Suarez meant by the ipso facto loss of office. What they meant is that the ipso facto loss of office occurs after the Church judges the Pope to be a heretic and before any additional juridical sentence or excommunication (which differs from Cajetan’s opinion). In other words, after the Church establishes 'the fact' that the Pope is a manifest heretic, he, according to this opinion, is deemed to lose his office ipso facto ('by the fact'). This is clear from the following quotation from Suarez who wrote:.....'"

Kramer, Paul. To deceive the elect: The catholic doctrine on the question of a heretical Pope . Kindle Edition.

St. Robert Bellarmine, whose feast day it is today, held that manifest heresy causes an immediate loss of office.  No judgment or declaration of the Church is needed for the loss of office to take place.  Why?  Because the Church teaches that the public sin of manifest formal heresy per se (i.e., by its very nature) separates the heretic from the Church.  This is the crux of the issue.

"It is unanimously explained by expert canonists and theologians that according to Opinion No. 4, a judgment must be made by the Church for the heretic pope to fall from office; and according to Opinion No 5, the heretic pope falls automatically by himself from the pontificate by the very act itself of manifest formal heresy, without any judgment being pronounced by the Church. Both of these opinions were already expressed by canonists in the early 1180s, as Moynihan docuмents in his earlier cited work. That essential difference which distinguishes between the fourth and fifth opinions was clearly understood by theologians and canonists in Bellarmine’s day. It simply beggars belief that anyone would seriously claim that the eminent scholars who have written unanimously on this question are wrong – that they have misinterpreted Bellarmine, and they have not understood Opinion No. 5 correctly. This is exactly what Salza & Siscoe do when they say that Suárez and Bellarmine are both of Opinion No. 5, which according to them, requires the judgment of the Church for the loss of office to take place. It is quite simplyinconceivable that Bellarmine would have been ignorant of the long established opinion which held that the pope who falls into heresy falls automatically by himself from the pontificate by the very act itself of manifest formal heresy, without any judgment being pronounced by the Church; and that he would have not included it as one of the five opinions. Either Salza & Siscoe do not understand Opinion No. 5, or Bellarmine did not understand it correctly; and that would mean that all of the expert commentators on the Five Opinions have not correctly understood it either!"

Kramer, Paul. To deceive the elect: The catholic doctrine on the question of a heretical Pope . Kindle Edition.

THIS ^^^.  Until tax attorney Salza came onto the scene, the distinction between Opinions 4 and 5 were well understood by all.  In fact, according to Salza, even St. Robert didn't understand it.  Thankfully, the ex-Mason tax attorney was around to correct St. Robert and everyone else.