If your public document is to be used in a country where the Apostille Convention does not apply, you should contact the Embassy or Consulate of the country where you intend to use the document in order to find out what your options are. This usually means that you need to present your documents to the said country’s Embassy or Consulate in the Philippines for its authentication/legalization. You may also ask the intended recipient of your document whether an Apostille is necessary in your particular case.