the current Service Contract System took effect in 1973 with the enactment of Presidential Decree No. 87, better known as the "Oil Exploration and Development Act of 1972". With its attractive contractual terms and liberal fiscal regime that are particularly favourable to offshore exploration, activities shifted to offshore areas like the Northwest Palawan Shelf where the first oilfield, Nido, was discovered. Several small fields, all located in offshore Northwest Palawan, were subsequently discovered and produced.