The industry in general works that if you do not have a separate commercial agreement, there are interline agreements where you are then paid a pro-rated amount of the fare of the passenger who is connecting based on either mileage or a portion of the fare.
Chez nous, en général, en l'absence d'un accord commercial distinct, il y a des accords intercompagnies en vertu desquels on reçoit un montant calculé au pro rata en fonction du kilométrage ou du tarif du voyageur en correspondance.