Rubuta ci gaba don wannan sakin layi - Ottaviani yana ɗaya daga cikin 'yan majalisa waɗanda suka halarci taron majalisar papal na 1963
, wanda ya zaɓi Giovanni Battista Montini a matsayin Paparoma Paul VI. Ya kuma kasance "protodeacon" (babban kardinal-deacon) a lokacin taron, kuma a matsayin haka, ya sanar da zaɓen Montini kuma ya naɗa shi a ranar 30 ga Yuni tare da triregnum.