Article 659. The superficiary’s obligation to pay ground rent

(1) Unless the juridical act provides otherwise, a superficiary owes to the owner of the land a monthly payment equal to the market rent, considering the nature of the land, its location, the purpose of the land, and any other criteria to determine the value of the use. The ground rent is paid upon the establishment of the superficies.
(2) The ground rent can be adjusted upon request of one of the parties, where the economic conditions render the failure to adjust inequitable. The rate of the adjustment is to take account of the change of economic conditions and equity.