Paternity challenge newly regulated

Bundestag adopts reform following Federal Constitutional Court’s requirements

On February 26, 2026, the Bundestag passed a reform of paternity challenging. The occasion was the decision of the Federal Constitutional Court on April 9, 2024 (Ref. 1 BvR 2017/21). The court had criticized key parts of the previous legal framework regarding descent and tasked the legislator with rebalancing the rights of biological fathers – while also taking into account the interests of the child and the existing social family.

At its core, it concerned the provision of § 1600 BGB and the previously widespread practice that a biological father often could not effectively challenge the legal paternity of another man if there was a social-family relationship between the legal father and the child. This could lead to biological fathers being permanently excluded, even if they wanted to take responsibility.

Why the old law was constitutionally problematic

According to the decision of the Federal Constitutional Court, the previous regulation did not meet the requirements of the Basic Law because it did not adequately consider the constitutionally protected parental position of biological fathers. Biological fathers must also be able to assert the protection of parental rights, insofar as a genuine effort to assume parental responsibility is made. The previous, heavily schematic blocking effect of the social-family relationship had prevented appropriate balancing in many cases.

Thus, the legislator was tasked with creating a procedure that does not solely rely on formal criteria but provides viable standards for balancing.

Child welfare as a guideline – but with more open balancing

The reform continues to center on child welfare. However, new is that in the future, the mere existence of a social-family relationship should no longer automatically lead to a challenge being excluded. Instead, a comprehensive consideration of the actual living conditions should take place. This particularly includes:

• the age of the child and their developmental stage,
• the intensity and stability of existing bonds,
• the actual assumption of responsibility by the involved adults,
• the anticipated consequences of a change in legal assignment for the child.

This opening aims at a more balanced reconciliation between the interests of the child, the biological father, and the legal family. The decision should be more case-specific and less characterized by rigid exclusion mechanisms.

“Second chance” for biological fathers under changed circumstances

Of significant practical importance is the introduction of a so-called “second chance.” Accordingly, a paternity challenge may be reconsidered at a later date if an initially existing social-family relationship between the child and the legal father ceases or significantly changes. This reform acknowledges that family constellations are not static and that bonds can develop or break.

While the previous legal state led to a permanent exclusion in many constellations, the new regulation provides the possibility to react to changed actual circumstances. This gives the biological father a realistic option to subsequently attain a legal parental position if this appears viable in the specific case.

Acknowledgments during ongoing proceedings: Avoiding contradictory decisions

The reform also stipulates that acknowledgments of paternity during ongoing judicial proceedings should be more restricted. The aim is to avoid contradictory status decisions and to stabilize the procedural situation. At the same time, the involvement of all parties should be strengthened to facilitate agreements and reduce conflicts early on.

The child’s role is also further emphasized: their bonds, their living reality, and the effects of a status change should be even more in focus.

Open balancing system instead of factual barriers

Biological fathers are supposed to gain better opportunities through the reform to enforce legal paternity even against existing allocations – but only if this is justified after a comprehensive balancing in the individual case. Thus, previous de facto exclusion mechanisms are pushed back, and replaced by an open balancing system.

At the same time, it remains that child welfare must not only be mentioned formally but must be significantly implemented in practical decisions. The possibility of a renewed challenge in changed circumstances reinforces this dynamic additionally.

More focus on individual cases – more demands on procedures and presentation

The stronger focus on individual cases also increases the demands on family court procedures. In practice, it will be crucial to nachvollig explain the actual bonds of the child, the lived family relationships, and the willingness of the biological father to take responsibility. This can make the application of the law more complex and decrease the predictability of individual decisions, as fewer general criteria apply.

It is also important to note: A paternity challenge affects the child’s status and has far-reaching consequences, for example, for maintenance, inheritance law, nationality issues, or custody and access arrangements. Therefore, in many cases, follow-up questions need to be clarified that go beyond the simple descent procedure.

Supplementary legal advice (for completeness)

• Deadlines and eligibility for challenges: In descent law, deadlines for challenges and the question of who is allowed to challenge play a central role. Which deadlines apply in individual cases and when they begin to run regularly depends on knowledge and circumstances and should be carefully checked.
• Genetic clarification:In contestation proceedings, biological descent is often decisive. Judicial clarification typically occurs through taking evidence (e.g., paternity reports) while respecting the procedural rights of those involved.
• Distinction from visitation and custody issues:While legal paternity affects rights and obligations, the topics of visitation and custody are decided in separate proceedings or according to separate criteria, again primarily focused on the child’s best interests.

Paradigm shift in paternity law

Overall, the reform marks a paradigm shift. Instead of rigid exclusion mechanisms, the legislator relies on a fundamental-rights-based individual assessment. For biological fathers, the possibilities to achieve legal parental status increase. At the same time, the child’s welfare remains the decisive touchstone of every judicial decision.

MTR Legal Attorneys supports with questions about paternity and other topics of family law.

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Note on presentation:This article serves general informational purposes and does not constitute individual advice. The legal situation may change; the circumstances of the specific case are decisive for its assessment.