This petition for review with prayer for a writ of preliminary injunction and/or restraining order filed by petitioners, Philippine Ports Authority ("PPA" for brevity), Port Manager Bienvenido Basco and the Port District Manager, Ernesto Fernando of Davao City, challenges the jurisdiction of the Regional Trial Court of Davao City, Branch 17, in a case involving the legality of port charges imposed by the PPA on the respondent Terminal Facilities and Services Corporation ("TEFASCO" for brevity). The port charges in question include: (1) 100% wharfage dues and berthing fees and (2) the 10% government share in arrastre/ stevedoring revenues and/or privilege fee, pursuant to Section 1213 of the Tariff and Customs Code.
The antecedent facts are:
On July 11, 1974, P.D. No. 505 was promulgated, creating the Philippine Ports Authority (PPA). The Decree was later amended by P.D. No. 857 dated December 23, 1975 (otherwise known as the Revised PPA Charter). Under the Decree, the PPA is entrusted with the function of carrying out an integrated program for the planning, development, financing and operation of ports and port districts throughout the country. The powers, duties and jurisdiction of the Bureau of Customs concerning arrastre operations were transferred to and vested in the petitioner PPA (Philippine Ports Authority vs. Mendoza, 138 SCRA 496, 503). Pursuant to said decree, PPA was authorized to "regulate the rates or charges for port services or port related services so that, taking one year with another, such rates or charges furnish adequate working capital and produce an adequate return on the assets of the Authority"(PPA) (Section 20[b] and "to levy dues, rates, or charges for the use of the premises, works, appliances, facilities, or for services provided by or belonging to the Authority or any other organization concerned with port operations" (Section 6[b] [IX]). Furthermore, the PPA was authorized to impose a ten percent (10%)