What are the formalities required in the execution of holographic will?

1. Signed by testator himself

2. Executed in a language or dialect known to him (Art. 804)

3. Entirely written

4. Dated;

Note: In case of any insertion, cancellation, erasure or alteration in a holographic will, the testator must authenticate the same by his full signature. (Art. 814)


What are the effects of insertions or interpolations made by a 3rd person?

General Rules:

When a number of erasures, corrections, cancellation, or insertions are made by the testator in the will but the same have not been noted or authenticated with his full signature, only the particular words erased, corrected, altered will be invalidated, not the entirety of the will.


1. Where the change affects the essence of the will of the testator; Note: When the holographic will had only one substantial provision, which was altered by substituting the original heir with another, and the same did not carry the requisite full signature of the testator, the entirety of the will is voided or revoked.

Reason: What was cancelled here was the very essence of the will; it amounted to the revocation of the will. Therefore, neither the altered text nor the original unaltered text can be given effect. (Kalaw v. Relova, G.R. No. L-40207, Sept. 28, 1984)

2. Where the alteration affects the date of the will or the signature of the testator.

3. If the words written by a 3rd person were contemporaneous with the execution of the will, even though authenticated by the testator, the entire will is void for violation of the requisite that the holographic will must be entirely in the testator’s handwriting.