Short answer. If the doubt touches only an incidental point, the law breaks the tie: in a gratuitous contract the least transmission of rights prevails, and in an onerous one the reading giving the greatest reciprocity of interests wins. If the doubt covers the principal object itself, Article 1378 of the Civil Code makes the contract null and void.
What the law says
If the doubts are cast upon the principal object of the contract in such a way that it cannot be known what may have been the intention or will of the parties, the contract shall be null and void.
Civil Code, Article 1378 — Doubts of Last Resort. Read the full provision →
A rule of last resort, not a first move
Article 1378 only comes into play when it is absolutely impossible to settle the doubt by every earlier rule of interpretation. Those rules come first: read the words in their ordinary sense, prefer the evident intention of the parties over the literal wording, read every clause together rather than in isolation, give an ambiguous term the meaning that makes the clause effective rather than useless, and read usage and the parties’ own conduct into the bargain. Only a doubt that survives all of that reaches this article, which is why it is invoked far less often than parties expect.
Gratuitous versus onerous contracts
Where the surviving doubt is about an incidental circumstance, the tie-breaker depends on the kind of contract. In a gratuitous contract — a donation, a loan of a thing for free use — the law prefers the least transmission of rights and interests, on the reasoning that someone giving something away should not be presumed to have given more than is clear.
In an onerous contract, where each side gives to get, the doubt is settled in favour of the greatest reciprocity of interests: the reading that keeps the exchange balanced, rather than one that hands a windfall to whichever party drafted more cleverly.
When the whole contract fails
The last sentence is the severe one. If the doubt goes to the principal object — which parcel of land was sold, what quantity or which goods were meant — so that nobody can tell what the parties actually willed, there is no contract to save and it is null and void.
That leaves both sides with nothing to enforce and with a restitution problem instead. The practical lesson is preventive: identify the object precisely, by title number, boundaries, model, quantity or specification, and attach the plan or schedule to the document. Ambiguity in the price or a deadline can usually be repaired by interpretation; ambiguity about the thing itself can destroy the whole agreement.
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.
- Merlinda Plana vs. Lourdes Tan Chiua and Heirs of Ramon Chiang, G.R. No. 250636, January 10, 2023 — read the decision on LawPhil →
- Heirs of Mary Lane R. Kim, represented by Kim Sung II, Janice Kim, G.R. No. 249247, March 15, 2021 — read the decision on LawPhil →
- Spouses Rene Luis Godinez and Shemayne Godinez vs. Spouses Andrew T. Norman and Janet, G.R. No. 225449, February 26, 2020 — read the decision on LawPhil →
- United Planters Sugar Milling Co., Inc. (UPSUMCO) vs. The Honorable Court of Appeals, et al, G.R. No. 126890, April 2, 2009 — read the decision on LawPhil →