During the Siege of Sinope, one of the sources states that Alexios has "grown sons in Trebizond who are capable of governing", so it is clear John was born before 1214.
Selama Pengepungan Sinop, salah satu sumber menyatakan bahwa Alexius memiliki "putra-putra dewasa di Trebizond yang mampu memerintah", jadi jelaslah Ioannes lahir sebelum tahun 1214.