Short answer. No. Article 367 of the Civil Code once gave natural children by legal fiction the father's surname, but the Family Code abolished that category along with the Civil Code's other sub-classes of children born outside marriage. A single class of illegitimate children exists today, with surnames governed by a later Family Code rule, as amended by Republic Act No. 9255.
What the law says
Natural children by legal fiction shall principally employ the surname of the father.
Civil Code, Article 367 — Surname of a Natural Child by Legal Fiction. Read the full provision →
What 'legal fiction' meant here
The term 'legal fiction' signaled that this class of child did not fit the ordinary definition of a natural child but received similar treatment anyway. The law extended natural-child status to certain children even though the actual circumstances of their parents did not meet that definition, and one consequence of that extended status was the surname rule Article 367 states.
The surname rule as originally written
Article 367 principally gave these children the father's surname, mirroring the rule Article 366 set for a natural child acknowledged by both parents. The word 'principally' left room for exceptions, but as enacted it made the father's surname the default outcome for this category rather than one that depended on separate acknowledgment by each parent individually or on the ordinary definition of a natural child.
Why the category is gone
The Family Code restructured how Philippine law classifies children born outside marriage. Articles 163 and 165 of the Family Code no longer distinguish a natural child, a natural child by legal fiction, or the Civil Code's other sub-classes; every child conceived and born outside a valid marriage is simply illegitimate. That restructuring removed the factual basis Article 367 depended on.
The rule that applies in its place
A later Family Code rule on surnames, as amended by Republic Act No. 9255, now sets the surname for every illegitimate child regardless of the circumstances that once separated a natural child from a natural child by legal fiction. The default is the mother's surname, with the father's surname available only where the recognition conditions Republic Act No. 9255 requires are met, typically an admission of paternity in the birth record or a later public or private document the father signs. This single rule binds every illegitimate child alike; it no longer matters whether a child's parents would once have been sorted into the natural-child, natural-child-by-legal-fiction, or another Civil Code sub-class, since that entire classification scheme no longer affects the surname a child ultimately carries.
Recognition and the modern registration process
A father seeking to have an illegitimate child carry his surname today follows the same documentary route under Republic Act No. 9255 no matter whether the child's circumstances would once have placed them in the natural-child-by-legal-fiction category. What mattered under Article 367, the parents' situation at the time the child was conceived, no longer sorts a child into a separate legal box; only the recognition procedure current law sets determines the surname outcome. That rule binds the local civil registrar processing the birth record or annotation, not just the parents, and a registrar who ignores it can be compelled to correct the record. A father who never completes the recognition steps cannot force his surname onto the child, and the mother's surname simply stands as the default until he does.
Related provisions
- Civil Code, Article 367 — Surname of a Natural Child by Legal Fiction
- Civil Code, Article 366 — Surname of an Acknowledged Natural Child