Paternity, Maternity, and Filiation

Filiation refers to the legal bonds that exist between parents and their children. Whether in relation to paternity or maternity, filiation generates bonds and relationships between individuals, and these bonds produce rights and duties.


What are the types of filiation?

Filiation is established by:

  • Natural or genetic ties
  • Assisted reproductive methods
  • Adoption
What is filiation by natural or genetic bonds?

It refers to the natural ties or the biological kinship between parents and their children. In other words, paternity or maternity is established by the natural act of conception and delivery (birth) from which parents derive take charge of their children.

What is filiation by assisted reproductive methods?

Also known as surrogacy, it refers to parenthood that is not established naturally or biologically. In these cases, the surrogate shares no genetic ties with the child born and, from the beginning, the surrogate’s intention was to carry the pregnancy to term (have a baby) so that another might claim filiation of the child.

What is filiation by adoption?

It refers to the legal proceeding to replace the natural or biological filiation of parents who do not want or cannot assume the responsibilities of paternity or maternity. Through this legal proceeding, the person’s existing and legally recognized family ties to their biological child is totally broken and is replaced with the filiation by those people who have expressed their will to legally assume all responsibilities concerning the child.

Does filiation determine a person's last names?

Yes, both filiation by natural or genetic ties and filiation by adoption will determine the child’s last names.

What rights arise from filiation?

With filiation, a child acquires the right to:

  • have the last name of each parent
  • receive support
  • the fulfillment of the duties arising from parental rights
  • inherit from their parents
How is filiation established?

There are different ways to establish filiation. In general terms, there is a presumption of paternity and maternity that establishes ties between parents and their children. These presumptions establish the bonds between people, unless proven otherwise. As a rule, childbirth determines maternity, except in cases of surrogacy and filiation by adoption.

On the other hand, when filiation is not established by the presumption of paternity or maternity, it must be established through a parent’s voluntary acknowledgment or by decree, either by a court or through administrative agency, specifically the Child Support Administration (ASUME, by its Spanish acronym).

What are the presumptions of filiation?

Regarding maternity, childbirth determines the mother-child relationship. However, this presumption does not apply when the birth is by a surrogate. In these cases, the surrogate shares no genetic ties with the child born and, from the beginning, the surrogate’s intention was to carry the pregnancy to term (have a baby) so that another may claim filiation of the child.

As for paternity, of the married woman’s spouse is presumed to be the father of the children born during the marriage or within 300 days following the dissolution of the marriage. In addition, paternity is presumed when the child is voluntarily acknowledged.

What are the effects of the presumptions of filiation?

These presumptions establish filiation unless there is proof to the contrary showing that such paternity or maternity is impossible. Until the presumption is rebutted, the parent who is presumed to have established filiation must fulfill the duties arising from it.

What is voluntary acknowledgement?

It is the voluntary expression made by one or both parents attesting that a person is their child. The voluntarily acknowledgement of a child by a parent may be carried out in many ways. Even the right and duty to acknowledge passes to the heirs if the parent dies before recognizing their child.

The voluntary acknowledgment can be made in writing, orally, or through actions that implicitly show the relationship between the parent and their child. A clear example of voluntary acknowledgement is by recording such filiation in the Vital Statistics Registry or in a will.
If the child is of legal age, however, they must consent to the voluntary acknowledgement. That is, the child of legal age cannot be acknowledged without their consent. In the case of children born of a surrogate, voluntary acknowledgment is the mechanism to establish the mother’s filiation.

A deceased child may also be acknowledged, but it is only effective if the child’s heirs give their consent personally or through their legal representatives.
Voluntary acknowledgement of children born out of wedlock can also be given in ASUME through a paternity certificate, without the need to be ratified by the court.

Can a paternity certificate be rescinded or set aside at a voluntary acknowledgment proceeding in ASUME?

Any of the parties signing a paternity certificate can rescind it or have it set aside within 60 days after the date it was signed. A petition to rescind the certificate must be filled out and submitted to the Vital Statistics Registry where the birth was recorded within 60 after the certificate was signed.

Any challenge to the paternity certificate after the 60-day rescission period has expired must be made in court and only on grounds of fraud, violence, intimidation, or material error of fact. The burden of proof will fall on whoever challenges the certificate. The legal duties of the party signing the certificate may not be suspended during the proceeding to challenge it in court, except for good cause shown.

Filiation Actions in Court

What are the legal actions related to filiation?

There are three kinds of legal actions concerning filiation:

  • action for filiation: a claim for a court to determine a person’s status as the son or daughter of their parents.
  • an action to challenge the presumption of paternity or maternity
  • mixed: an action to challenge filiation and to affirm or establish another (a mixed action seeks to establish the paternity or maternity of one person over another, for which biological evidence can be presented)
When can an action for filiation be filed?

Any person may request that their status as the son or daughter of any of their parents be decreed by a court during the lifetime of the latter. However, if the parent has died, the action against the heirs must be filed within a period of 2 years after the death of the parent, except in the following circumstances:

  • If the parent dies while the child is a minor or during the total incapacity of the child, the action must be filed by said child within 4 years after becoming of legal age (turn 21 years old) or the end of the incapacity.
  • If after the death of the parent there is any document or material evidence in which the child is expressly acknowledged, this person must file the action within 1 year after finding such statement or becoming aware of such evidence.
Who can file actions for filiation?

This will depend on the type of action. If it is the traditional action for filiation, the child can file the action through:

  • the parent who acknowledged them
  • the guardian, if the child is a minor or incapacitated
  • on their own behalf, if they are of legal age
  • their heirs, if they passed away

On the other hand, the action to challenge maternity can only be brought under the following circumstances: simulation of childbirth, surrogacy, or substitution of the child during or after birth. This action to challenge maternity can be filed by:

  • the alleged parent
  • the biological mother
  • the child, on their own behalf if they are of legal age, or through a legal representative or guardian ad litem when the child is a minor or incapacitated
  • the intended mother through a surrogate
  • the alleged father
  • if the woman that is presumed to be the mother of the child files the action to challenge maternity, a guardian ad litem must be appointed for the child

As for paternity, it may be challenged by:

  • the alleged father
  • the mother
  • the child, on their own behalf if they are of legal age, or through a legal representative or guardian ad litem when the child is a minor or incapacitated
  • the biological father
  • the intended father
How is an action for filiation filed?

These causes of action may be commenced in court. When filiation is sought in order to apply for child support, it must be filed through an administrative proceeding before ASUME.

What evidence must be presented in court?

Filiation can be established by any admissible evidence. However, it is preferable to bring scientific tests recognized and accepted by the scientific community as appropriate and reliable to determine paternity or maternity, provided that they are conducted by competent experts under the best clinical criteria.

In any legal action in which a person’s paternity or maternity is disputed, the judge—on their own initiative or at the request of a party, legal guardian, or guardian ad litem and within the terms established by law—may order that the presumed parent and the child undergo genetic testing.

Who covers the costs of genetic testing?

If the test results are positive, the alleged biological father or mother will assume the costs. However, if the test results are negative, the person who requested the test will assume the costs.

Can an objection to the genetic testing be filed?

Yes. Where the results of a genetic test suggests a 95% to 97.9% probability of paternity or maternity, an objection may be filed. In these cases, this result will be evaluated together with the other evidence in the record.

Paternity will be presumed incontrovertible (which cannot be objected) if the test produces a result of 98% probability or higher. This means that no evidence to the contrary may be presented.

The results of the tests will be subject to the scrutiny of the Court, who will consider whether they were carefully carried out by experts and whether they were adequately supervised.

What happens if the genetic test is negative, but child support has already been paid?

Where the test is negative, the obligee (the minor or other person who by law is entitled to receive support) or the person in charge of the obligee must return the amount received as support.

What happens once filiation is established?

If filiation is established as part of a court proceeding, the judge will order that the child be registered in the Vital Statistics Registry with the proper last names. In addition, the rights and duties concerning support and visitation arise as of the date of filiation decreed by a court.

A claim for damages due to lack of voluntary acknowledgment is actionable and may be granted by the court.

What can be done if a person fails to pay child support or exercise visitation?

Where a person has been ordered by a court to pay child support or to exercise visitation as provided therein but fails to do so, a motion may be filed alleging noncompliance. Once the motion is filed with the Office of the Clerk of the Court, a hearing will be set to determine whether, in fact, the person has failed to comply with the court order. Both parties must appear for said hearing to support their allegations. In addition, proof of the debt, support payments, or noncompliance with the visitation plan must be brought.

Revised: March 2023