- Petitioner
- Sebastian Siga-An
- Respondent
- Alicia Villanueva
- Citation
- G.R. No. 173227
- Court
- Supreme Court
- Division
- Third Division
- Ponente
- Chico-Nazario, J.
- Decided
- January 20, 2009
Summary
This Supreme Court case involves a loan dispute between military officer Sebastian Siga-an and businesswoman Alicia Villanueva. Villanueva sued for return of P660,000.00 in excess payments made on a P540,000.00 loan, claiming no valid interest agreement existed. The Court applied Article 1956 of the Civil Code requiring written stipulation for monetary interest, finding that the promissory note was executed under coercion and did not constitute valid agreement. Under the principle of solutio indebiti, the Court ordered restitution of overpayments but reduced the amount to P335,000.00 based on proven payments. The decision reinforced the strict requirement for written interest agreements in loan contracts and the application of unjust enrichment principles when payments are made without legal basis.