we don't, we'll only know for sure when 15/16 accounts will be published, but best guess would be appearance based. €2m incentive to Genoa to play him regularly 'for his development' and a further €3.5m if he plays well for Juve + Juve wins Scudetto etc so he could cost €11m if he turns good. 'good' here probably means he becomes good rotation player or one of Juve's current star midfielders would be sold and Sturaro becomes a starter (which to me is not a good thing).

