Short answer. Yes. Article 1361 provides that when a mutual mistake of the parties causes the instrument to fail to disclose their real agreement, the instrument may be reformed. Since you both shared the same mistake, either of you may ask a court to reform the document to reflect what you actually agreed.
What the law says
When a mutual mistake of the parties causes the failure of the instrument to disclose their real agreement, said instrument may be reformed.
Civil Code, Article 1361 — Reformation for Mutual Mistake. Read the full provision →
Reformation exists precisely for this kind of shared error
Article 1361 addresses exactly the situation you describe: when a mutual mistake of the parties causes the failure of the instrument to disclose their real agreement, said instrument may be reformed. Reformation is a remedy aimed at the written instrument itself, not at the underlying agreement between you and your partner. The premise is that your actual meeting of the minds was correct, but the document meant to record that agreement failed to capture it accurately because you both made the same mistake when it was drafted.
Why the mistake being shared, rather than one-sided, matters here
The article specifically requires a mutual mistake, meaning both of you were laboring under the same misunderstanding about what the instrument said or should have said. This is different from a situation where only one party misunderstood the terms while the other understood them correctly, which raises separate questions about whether there was genuine consent to begin with. Because your mistake was shared, the underlying agreement itself is not in doubt; what needs correcting is purely the instrument's failure to express what you both actually intended.
Why either party may bring the action
Since the mistake belongs to both of you equally, and the resulting inaccuracy in the instrument affects both of your rights under the agreement, either party has standing to ask a court to correct the document. Reformation is not a remedy reserved for whichever party is more disadvantaged by the error; both of you share an interest in having the written instrument actually reflect what you both agreed to, so either of you can initiate the process to have it corrected.
What reformation actually changes
Reformation does not create a new agreement between you and your partner; it corrects the written instrument so that it matches the real agreement you both already had in mind. Anyone pursuing this remedy should be prepared to establish what the true agreement actually was and how the mutual mistake caused the instrument to depart from it, since the court's role is to bring the document back in line with what you both genuinely intended, not to rewrite the substance of your bargain.
Cases citing this provision
These Supreme Court decisions cite the provision above. We list them so you can read them yourself; the summaries of what each decided are not ours to give.
- Globe Asiatique Relaty Holdings Corporation vs. Union Bank of the Philippines, G.R. No. 229339, July 29, 2019 — read the decision on LawPhil →