Short answer. Because Article 166 grades the penalty by whose currency was forged. Forging an obligation or security of the Philippines draws the heaviest bracket, reclusion temporal, while forging a note issued by a foreign government or a foreign bank falls into much lighter brackets, arresto mayor or a shorter prisión mayor term.
What the law says
By reclusion temporal in its minimum period and a fine not to exceed two million pesos (₱2,000,000), if the document which has been falsified, counterfeited, or altered is an obligation or security of the Philippines.
Revised Penal Code, Article 166 — Forging Notes Payable To Bearer. Read the full provision →
What the law says
By arresto mayor in its medium period and a fine not to exceed one million pesos (₱1,000,000), if the falsified or counterfeited document was issued by a foreign government.
Revised Penal Code, Article 166 — Forging Notes Payable To Bearer. Read the full provision →
What the law says
By prisión mayor in its minimum period and a fine not to exceed Four hundred thousand pesos (₱400,000), when the forged or altered document is a circulating note or bill issued by a foreign bank duly authorized therefor.
Revised Penal Code, Article 166 — Forging Notes Payable To Bearer. Read the full provision →
One article, four different penalties
Article 166 does not punish every act of forging paper currency the same way. It sets out four separate penalty brackets in one article, and which bracket applies turns on whose obligation or currency was forged, not on how skillfully the forgery was made or how much was produced. The heaviest bracket applies when what was forged is an obligation or security of the Philippines — Philippine treasury notes, national bank notes, and similar government-issued paper. The lightest brackets apply when what was forged is a note issued by a foreign government or a foreign bank. The peso amounts below reflect Republic Act No. 10951 (2017), which revised the fines this article carries; older printings of the Code still show the pre-2017 figures.
Forging a Philippine treasury note
Forging, falsifying, or altering an obligation or security of the Philippines carries the heaviest penalty in the article: reclusion temporal in its minimum period and a fine not to exceed two million pesos, if the document which has been falsified, counterfeited, or altered is an obligation or security of the Philippines. This bracket is not limited to treasury notes by name — the article defines that phrase broadly, covering bonds, certificates of indebtedness, national bank notes, treasury notes, and other government-issued instruments of value. Reclusion temporal alone runs into years of imprisonment, which is why forging the state's own currency or debt instruments draws by far the harshest bracket in Article 166.
Forging a foreign government's currency
A note issued by a foreign government sits in a much lighter bracket: arresto mayor in its medium period, with a fine not to exceed one million pesos, if the falsified or counterfeited document was issued by a foreign government. Arresto mayor is a far shorter term of imprisonment than reclusion temporal, even though the fine ceiling here can still reach one million pesos. The gap between this bracket and the one for Philippine obligations is mainly about the prison term, and it is the clearest illustration in the article of how much lighter forging a foreign government's own currency is treated compared with forging the country's own.
Where a foreign bank's banknote fits
The article separately covers a circulating note or bill issued by a foreign bank duly authorized to issue it, punished by prisión mayor in its minimum period and a fine not to exceed four hundred thousand pesos. That sits between the other two foreign-related brackets in prison term: longer than the bracket for a foreign government's own note, but still well short of the reclusion temporal bracket reserved for the Philippines' own obligations and securities. A circulating note issued by a domestic banking association has its own separate, heavier bracket again, at prisión mayor in its maximum period and a fine not to exceed one million pesos.