G.R. No. L-28967 July 22, 1975
AMELIA G. TIBLE, petitioner-administratrix, vs. JOSE C. AQUINO, respondent-claimant.

FACTS

Amelia G. Tible, as administratrix of the intestate estate of the late Congressman Emilio M. Tible, sought the review of a Court of Appeals decision reversing the probate court’s order. The trial court had dismissed Jose C. Aquino’s claim for P30,000 against the estate and instead ordered Aquino to pay the estate P50,500. The claim, filed nearly eleven months after the first publication of the notice to creditors, was based on promissory notes executed by the deceased. The core dispute centered on a 1955 transaction involving a portion of Aquino’s forest concession in Agusan. Aquino’s version was that Tible bought the land for P107,000, had paid P50,000, and owed a P30,000 balance evidenced by promissory notes. The administratrix countered that the true sale price was only P50,000 (already paid) and that the promissory notes for P30,000 represented a conditional increase, dependent on Tible’s operation of the concession, with Aquino being indebted to Tible for separate cash advances.

ISSUE

The primary issue was whether the Court of Appeals erred in reversing the trial court and upholding the validity of Aquino’s claim for P30,000 based on the promissory notes.

RULING

The Supreme Court affirmed the decision of the Court of Appeals. The legal logic rested on two key points. First, the Court upheld the appellate court’s factual finding that the promissory notes represented the true balance of the purchase price for the timberland, not a conditional obligation. Critically, the Court agreed with the legal conclusion that any alleged condition making payment dependent solely upon Tible’s will to operate the concession was void under Article 1115 of the Civil Code. An obligation cannot be made to depend exclusively on the debtor’s whim. Second, the Court rejected the administratrix’s new theory, raised only on appeal to the Supreme Court, that the underlying sale was void for being contrary to law and public policy. A party cannot change its theory of the case on appeal after receiving an unfavorable judgment; the administratrix had previously asked the appellate court to affirm the trial court’s order which itself recognized the validity of a sale, albeit under a different price arrangement. The belated challenge to the claim’s timeliness was also deemed waived, as the administratrix had actively litigated the merits by filing a substantial counterclaim without previously contesting jurisdiction on that ground.