Short answer. Yes. Article 136 of the Revised Penal Code, as amended by RA 10951, imposes a heavier penalty for conspiracy to commit rebellion — prisión correccional in its maximum period — than for proposal — prisión correccional in its medium period. Both carry a fine of up to one million pesos or four hundred thousand pesos respectively.
What the law says
The conspiracy and proposal to commit rebellion or insurrection shall be punished respectively, by prisión correccional in its maximum period and a fine which shall not exceed One million pesos (₱1,000,000) and by prisión correccional in its medium period and a fine not exceeding Four hundred thousand pesos (₱400,000).
Revised Penal Code, Article 136 — Conspiracy To Commit Rebellion. Read the full provision →
Two separate acts, two different penalties
Article 136 of the Revised Penal Code distinguishes between two preparatory acts related to rebellion: conspiracy and proposal. A conspiracy exists when two or more persons agree to commit rebellion and decide to carry it out. A proposal occurs when a person who has decided to commit rebellion proposes its commission to others but no agreement to act is yet formed. Article 136 assigns a heavier penalty to conspiracy — it involves concerted commitment — and a lighter penalty to mere proposal, which is the earlier and less definite stage.
Current penalties as amended by RA 10951
Under the current text of Article 136, as amended by Republic Act No. 10951 in 2017: conspiracy to commit rebellion or insurrection carries prisión correccional in its maximum period and a fine not exceeding one million pesos. Proposal to commit rebellion or insurrection carries prisión correccional in its medium period and a fine not exceeding four hundred thousand pesos. The article also separately covers coup d'état: both conspiracy and proposal to commit it are punished at the higher level of prisión mayor in its minimum period with a fine of up to one million pesos. Older printings of the Penal Code still carry the original 1930 figures — verify which version your source is citing.
Why the distinction between conspiracy and proposal matters
The heavier punishment for conspiracy reflects the fact that a conspiracy is an agreement — a meeting of minds that has produced a collective decision to act. It is closer to the commission of the crime than a mere proposal, which is a one-sided offer that has not yet been accepted. Once two or more persons have agreed to carry out the rebellion, the crime of conspiracy is complete even if the actual rebellion never occurs. A proposal that is refused or ignored may end there. The criminal law recognizes this difference in dangerousness by grading the penalties accordingly.
These are preliminary offenses, not the rebellion itself
Article 136 punishes preparatory acts — what happens before any rebellion takes place. The actual offense of rebellion or insurrection, if committed, carries its own and generally heavier penalties under separate provisions of the Revised Penal Code. A person prosecuted under Article 136 for conspiracy or proposal to rebel has not yet participated in a rebellion; the offense is the agreement or the offer, which the law punishes independently because of the danger they represent. This is one of the relatively few instances in Philippine criminal law where preparatory acts are themselves made criminal.