Spouses Delia P. Ibañez v. Herminia S. Astorga

Summary

This property dispute involved competing claims over real estate in San Mateo, Rizal. Herminia validly purchased the property from Delfin in 2000 and took possession, building improvements and paying taxes. However, Delfin's sister Delia later allegedly forged his signature on a deed selling the same property to her in 2002, enabling her to obtain registered title. The Supreme Court affirmed lower courts' findings that the petitioners were not purchasers in good faith, as they had constructive notice of Herminia's prior possession and rights. The Court applied Article 1544 of the Civil Code, emphasizing that the double sale rule protects only good faith purchasers, and that registration in bad faith confers no valid rights. The decision reinforces the principle that prospective buyers must exercise due diligence in investigating property ownership, especially when the seller is not in possession, and that mere registration without good faith cannot validate an otherwise invalid transaction.