Using the Mother’s Middle Name for an Illegitimate Child

(Philippine legal perspective, updated to 30 April 2025)

1. Why middle names matter in Philippine civil status

In local civil-registry practice, a middle name identifies a person’s maternal lineage, while the surname (last name) identifies paternal lineage (for legitimate children) or, by default, the mother (for non-marital children) (Legal Amendment to Child's Name in Illegitimacy Cases). Because names are juridical attributes, the rules on when – or whether – an illegitimate child may carry a middle name are set by statute, Supreme Court jurisprudence, and PSA/LCRO (local civil registrar) issuances.

2. Statutory framework at a glance

Rule-set	Key provision	Effect on a non-marital child’s name
Family Code, Art. 176	Child is under the mother’s parental authority and “shall use the mother’s surname” unless RA 9255 applies.	Default: no middle name; last name = mother’s surname. (Using Mother's Surname as Middle Name for Illegitimate Child)
RA 9255 (2004) + 2016 Revised IRR	Allows an acknowledged illegitimate child to use the father’s surname upon compliance with an Affidavit to Use the Surname of the Father (AUSF).	Once the father’s surname is used, the child’s middle name becomes the mother’s surname. ([Republic Act No. 9255
RA 9858 (2009) & Arts. 177–182, Family Code	Legitimation by subsequent marriage (or when parents were below marrying age).	Child becomes legitimate; naming follows Art. 363 & 364—middle name is mother’s maiden surname. (R.A. 9858 - The Lawphil Project, G.R. No. 250199, February 13, 2023, - The Lawphil Project)
RA 11642 (2021) & RA 11222 (2019)	Administrative/Simulated-birth adoption laws.	Once adopted/rectified, child may adopt father’s surname and the mother’s surname as middle name, subject to court/DSSD approval.

3. Default scenario: father not acknowledged

Certificate of Live Birth (COLB)
Given name – chosen by the mother
Middle name – left blank
Surname – mother’s surname (her maiden surname if single, or married surname if married)
PSA Memorandum 30 June 2009 bars LCROs from later “supplying” the missing middle name in this situation (No Middle Name | Philippine Statistics Authority - rsso08.psa.gov.ph).
Why the mother’s own middle name cannot be inserted
- Doing so falsely implies that the mother (and not the unknown father) is the child’s paternal line, creating confusion in school, passport, and estate proceedings (Can An Illegitimate Child Use His Father’s Last Name? - PSAHelpline.ph).
- Any “correction” adding a middle name here alters filiation and therefore requires a Rule 108 judicial proceeding, not an administrative RA 9048 petition.

4. When the father recognizes the child (RA 9255 route)

Requirement	Where filed	Documentary basis
AUSF or Private Hand-written Instrument (PHI) acknowledging paternity	LCRO of place of birth (or PSA-Office of the Civil Registrar General for out-of-town)	Sec. 5, 2016 IRR of RA 9255
Child (if ≥ 18 yrs) must give written consent; if < 7 yrs, mother signs; 7–18 yrs: child countersigns	Same	IRR, Rule 4

Effect on the name:

Surname changes to father’s surname (annotated on COLB).
Middle name automatically becomes the mother’s surname – it need not be petitioned separately (Republic Act No. 9255 | Philippine Statistics Authority).
A supplemental report suffices if the middle name was blank on the original COLB (Can An Illegitimate Child Use His Father’s Last Name? - PSAHelpline.ph).

Important: Neither parent can later force the child to carry or drop the father’s surname; the Supreme Court in Grande v. Antonio (G.R. 206248, 18 Feb 2014) held that the choice ultimately belongs to the child (Use of father’s surname, the child’s decision | DivinaLaw).

5. Jurisprudence on using the mother’s surname as middle name

Case	Gist	Take-away
In re Adoption of Stephanie Nathy Astorga Garcia (G.R. 148311, 31 Mar 2005)	Upon adoption by her natural father, the child was allowed to use her natural mother’s surname “Garcia” as middle name and her father’s surname “Catindig” as last name.	The Court treated adoption as making the child legitimate; best-interest test prevails. (G.R. No. 148311. March 31, 2005 - The Lawphil Project)
Herrera v. CA (G.R. 164041, 29 Jul 2005)	Unacknowledged illegitimate child cannot motu proprio adopt the father’s surname or a middle name; must follow statutory process.	Reinforces that name changes affecting filiation need judicial/Rule 108 route. (G.R. No. 164041. July 29, 2005 - The Lawphil Project)

No decision requires an illegitimate child to bear a middle name; the rule is simply that the space stays blank unless and until (a) the father’s surname is carried under RA 9255/legitimation/adoption or (b) the child attains legitimacy.

6. Legitimation & adoption pathways

Legitimation by subsequent marriage (Arts. 177–182, Family Code; RA 9858)
- Requires that parents were free to marry each other at conception (ordinary legitimation) or were below 18 yrs at conception (RA 9858).
- Once legitimated, the child’s middle name becomes the mother’s maiden surname, identical to a legitimate child (G.R. No. 250199, February 13, 2023, - The Lawphil Project).
Administrative or court adoption (RA 11642 / RA 11222)
- After adoption order/decision, the court (or NACC for administrative cases) specifies the child’s complete new name; the usual pattern is [Given] + [Mother’s maiden surname] (middle) + [Adopting father’s surname] unless the decree states otherwise.

7. Correcting or adding a middle name: procedural map

Scenario	Appropriate remedy
Blank middle name because father not acknowledged (wanting to insert mother’s surname)	Not allowed under PSA Memo 30 Jun 2009; must retain blank. ([No Middle Name
Father later recognizes & signs AUSF	File AUSF; LCRO annotates COLB, middle name auto-populates.
Legitimation or adoption granted	Petition LCRO/PSA for annotation attaching the decree; LCRO issues amended COLB.
Erroneous middle name (e.g., typo) when one already exists	Correction under RA 9048/10172 (administrative) if change is clerical; otherwise Rule 108.

8. Practical implications

Travel & passports – DFA requires that the name on the passport match the PSA-issued COLB; mismatched middle names delay issuance.
School records & PhilSys ID – Educational institutions and PSA both adhere strictly to the recorded name; subsequent corrections must be reflected in Form 137/138.
Inheritance – An illegitimate child’s legitime is ½ of a legitimate child’s share (Art. 895, Civil Code). A blank middle name does not bar inheritance, but proof of filiation is essential (G.R. No. 157043 February 2, 2007 - The Lawphil Project).

9. Frequently-asked questions

Question	Short answer
Can I simply “add” my mother’s middle name through a local-registry correction?	No. Adding a middle name where none existed changes filiation and needs either AUSF (if father recognizes) or a court petition.
My child has my surname (mother) as both middle and last names after adoption—allowed?	Yes, as in Garcia case, if the adoption decree so provides and the court finds it in the child’s best interest.
We want to drop the father’s surname later—possible?	Only the child, once of age, may decide to revert to the mother’s surname; he/she must file a Rule 103 change-of-name petition.

10. Key take-aways

Blank by default: If the father is not legally acknowledged, the “middle name” box stays empty.
Mother’s surname becomes the middle name only when the child lawfully acquires the father’s surname (RA 9255) or becomes legitimate/ adopted.
No shortcut fixes: PSA memoranda forbid administrative insertion of the mother’s middle name in a purely non-marital birth. Judicial or statutory processes (AUSF, legitimation, adoption, Rule 108) are the only routes.
Child-centered approach: Supreme Court jurisprudence (e.g., Grande, Garcia) stresses the primacy of the best interests of the child and the child’s own right to decide once competent.

This article synthesizes the latest statutes, Supreme Court rulings, and PSA regulations effective as of 30 April 2025.