Well-settled is the rule that expert opinion is never conclusive. Courts may exercise discretion in accepting or overruling the opinions of handwriting experts. Clear and convincing evidence is required to overturn the presumption of validity of a notarized deed of absolute sale. Absent such species of evidence, the presumption stands.

Well-settled is the rule that expert opinion is never conclusive. Courts may exercise discretion in accepting or overruling the opinions of handwriting experts. Clear and convincing evidence is required to overturn the presumption of validity of a notarized deed of absolute sale. Absent such species of evidence, the presumption stands.

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In this case, petitioner failed to present clear and convincing evidence to overcome the presumption of validity of the notarized Deed conveying the land to private respondents. Her testimony denying the validity of the sale, having been “made by a party who has an interest in the outcome of the case, is not as reliable as written or documentary evidence. Moreover, self-serving statements are inadequate to establish one’s claims. Proof must be presented to support the same.”^[19]

LEONORA CEBALLOS, PETITIONER, VS. INTESTATE ESTATE OF THE LATE EMIGDIO MERCADO AND THE HEIRS OF EMIGDIO MERCADO, RESPONDENTS.