3rd-Party Determination, A1309-1310 Civil Code

1. Concept

Article 1309. The determination of the performance may be left to a third person, whose decision shall not be binding until it has been made known to both contracting parties. (n)

Article 1310. The determination shall not be obligatory if it is evidently inequitable. In such case, the courts shall decide what is equitable under the circumstances. (n)

2) These articles from the Civil Code refer to contracts where the specific details of performance (like the price of a house or the quantity of goods) are decided by an independent third party rather than the buyer or seller. (Google Gemini 3 [2025], reviewed by Legal / J. Del Puerto, Accessed 27 December 2025)

2) This is often done when neither party can agree on a value, or when specialized expertise is required to set a fair standard. (Ibid.)

3) Key Principles:

• Notification is Mandatory: Under Article 1309, the third party’s decision is just a proposal until both parties are informed. It doesn’t legally “lock in” until they know about it. (Ibid.)
• The “Fairness” Guardrail: Under Article 1310, the law protects parties from decisions that are “evidently inequitable” (grossly unfair). (Ibid.)
• Judicial Intervention: If the third party picks a value that is clearly biased or absurd, the parties can go to court, and a judge will determine a fair “equitable” value instead. (Ibid.)

Example 1: The Professional Appraiser (Real Estate). Imagine you want to buy your neighbor’s ancestral land, but neither of you knows the current market value. You both agree in a contract that “the price will be determined by ABC Appraisal Firm.” (Ibid.)

• Article 1309: The firm values the land at Php1M. You are not obligated to pay that Php1M until the firm sends the official report to both you and the neighbor. (Ibid.)
• Article 1310: If the firm values the land at Php10M (when all surrounding lots are worth Php1M), the court can set aside that price because it is “evidently inequitable.” (Ibid.)

Example 2: The Agricultural Harvest (Commodities). A juice factory agrees to buy an entire orange harvest from a farmer. Since the quality of the oranges varies, they agree that a neutral agricultural expert will determine the final price per kilo based on the sugar content after the harvest. (Ibid.)

• Article 1309: Once the expert tests the crop and decides the price is Php2/kg, the contract becomes binding the moment both the farmer and the factory are notified. (Ibid.)

Example 3: The Art Restorer (Services). A museum hires a specialist to restore a damaged painting. Because the extent of the damage is unknown, the contract states that an independent curator from a national gallery will determine the final “performance fee” once the work is 50% complete. (Ibid.)

• Article 1310: If the curator decides the restorer should be paid Php500,000 for five hours of basic cleaning—a price far beyond industry standards—the museum can challenge this in court. The court will then determine a fee that is “equitable” based on the restorer’s actual labor and skill level. (Ibid.)