definiens: with respect to a country shall mean, subject to Section XII(F ), an a mount equal to * * * * * as is determined in good faith by the agreement of the parties following the deliv ery of the notice described in this Section XVII(A ) ( 3 ) ( which amount shall be an amount that, on the basis of - 80 - market and other conditions prevailing at such time could reasonably be expected to be paid for * * * * * by a third party in an arm ’s -length transaction ) ; provided, however, that in the event that the parties can not in good faith agree upon the amount of the P atent Extension Payment within thirty ( 30 ) calendar days of the delivery of such notice, the amount of the Patent Extension Payment shall be the amount equal to the sum of each party ’s proposed Patent Ex tension Payment divided by two ( 2 ), except that if there is more than a * * * * * difference between such amounts, the amount shall be conclusively determined by a mutually agreed internationally rec ognized investment banking firm . If the parties can not so agree on one investment banking firm, eac h party will designate its own investment banking firm and such investment banking firms will jointly appoint a third investment banking firm . The cost of such third investment banking firm shall be born e one - half by each party . The investment banking firm appointed pursuant to this Section XVII(A)(3 ) will choose one of the parties ’ positions with respect to the amount of the Patent Extension Payme nt within thirty ( 30 ) days of its appointment