Preterition: neither instituted as heir nor expressly disinherited

Article 854 of the Civil Code partly provides: "[t]he preterition or omission of one, some, or all of the compulsory heirs in the direct line, whether living at the time of the execution of the will or born after the death of the testator, shall annul the institution of heir; but the devises and legacies shall be valid insofar as they are not inofficious."

As explained by Justice Eduardo P. Caguioa:Preterition consists in the omission in the testator's will of a compulsory heir in the direct line or anyone of them either because they are not mentioned therein or although mentioned they are neither instituted as heir nor expressly disinherited. The act of totally depriving a compulsory heir of his legitime can take place either expressly or tacitly. The express deprivation of the legitime constitutes disinheritance. The tacit deprivation of the same is called preterition. x x x[1]

In order that there be preterition, it is essential that the heir must be totally omitted. This is clear from the wording of this article in conjunction with Article 906.[2][3]

Summarizing, therefore, total omission means that the omitted compulsory heir receives nothing under the will, whether as heir, legatee or devisee, has received nothing by way of donation inter vivos or propter [nuptias], and will receive nothing by way of intestate succession.[4]

ADDITIONAL READINGS: 

[1] Eduardo P. Caguioa, COMMENTS AND CASES ON CIVIL LAW CIVIL CODE OF THE PHILIPPINES Vol. III (1970 3rd Ed.) at 154-155, citing 6 Manresa, 6th ed., p. 340; Neri v. Akutin, 74 Phil. 185 (1943).
[2] CIVIL CODE, Art. 906 provides: ART. 906. Any compulsory heir to whom the testator has left by any title less than the legitime belonging to him may demand that the same be fully satisfied.
[3] Eduardo P. Caguioa, COMMENTS AND CASES ON CIVIL LAW CIVIL CODE OF THE PHILIPPINES Vol. III (1970 3rd Ed.), pp. 155.
[4] Id. at 157.