hi,
when we are registering our players for champions league, we must include at least 4 player from our academy..
at first, i think the player who's called from our academy is player which their first team is our club.. but i think my conclusion is wrong since my last 2 season..
i played with inter, after i finished my first season, i added some of my u20 players to first team, and 2 of them is andreolli and balotelli.. i think these 2 players is exclude from 'academy player' criteria because their first club is not inter.. even i bought andreolli from co-ownership with roma..
but when i must register my player for champions league, i was little but surprised -but feel lucky indeed- because andreolli is a player who trained by inter; otherwise balotelli just as a player who trained in italy..
but the next season, once more i was surprised and got a fortune because my balotelli suddenly became a player who trained by inter

does anyone know for sure about the criteria of player who trained by our club?

I think they just need 3 years training with your club before the age of 21