P.R. Laws tit. 31, § 2236
A closed will found in the domicile of the testator with the cover torn, or the seals broken, or the signatures authenticating it effaced, erased, or corrected is presumed to be revoked.
This will, however, shall be valid should it be proven that this damage occurred without the wish or knowledge of the testator, or should the latter be insane; but, if the cover is found torn and the seals broken, it shall be necessary furthermore to prove the authenticity of the will in order that it may be valid.
If the will is found in the possession of another person, it shall be understood that the damage was caused by such person, and it shall not be valid unless its authenticity is proven if the cover is torn or the seals broken; and if both are intact, but with the signatures effaced, erased, or corrected, the will shall be valid unless it be proven that the instrument was delivered in this condition by the testator himself.
History —Civil Code, 1930, § 673.