Section 14 of Presidential Decree No. 1529, the following persons may file in the proper Regional Trial Court an application for the registration of title to land, whether personally or through their duly authorized representatives:
1. Those who by themselves or thru their predecessors-in-interest have been in open, continuous, exclusive and notorious possession and occupation of alienable and disposable lands of the public domain under bonafide claimof ownership since June 12, 1945, or earlier;
2. Those who have acquired ownership of private lands by prescription under the provisions of existing laws;
3. Those who have acquired ownership of private lands or abandoned river beds by right lands of accession or accretion under the existing laws;
4. Those who have acquired ownership of land in any other manner provided by law.