Trojan and Mirin: from Recognition Principle to Replication of Status

Two recent Grand Chamber judgments of the Court of Justice suggest that the “principle of recognition” in international family law has undergone a qualitative shift: It does more than set vague limits on the outcomes reached by the national laws of Member States. Instead, read together, Mirin and Cupriak-Trojan establish a broad principle of free movement of civil status.

This post sketches how the shift brought about by these two decisions could be translated into a doctrinal structure of private international law (PIL). I propose to call it “replication of status” (German: Statusnachvollzug) — a label intended to be precise about both the technique and its limits.

What Changed in Mirin and Cupriak-Trojan

The Court of Justice has long interpreted the right to free movement to require the stability of certain status questions across borders — first and foremost in its case law on names (starting with Grunkin-Paul). In family matters, the earlier case law on same-sex marriage (Coman) and parenthood (Pancharevo) was restricted to the recognition of specific effects these status relationships may entail, especially residence rights. However, those judgments did not concern the recognition of a civil status “as such”. Moreover, they related to status relationships involving non-EU nationals. It therefore remained unclear whether the restrictions would also apply to status relationships between Union citizens.

Mirin and Cupriak-Trojan have not only provided clarification but have also raised the Court´s jurisprudence to a new level. Mirin establishes the requirement to give cross-border validity to a gender entry that was changed in another Member State. Cupriak-Trojan requires Member States, as a matter of principle, to recognise a same-sex marriage lawfully concluded and registered in another Member State. This recognition is required even if the national laws of the requested Member State do not consider the status valid.

Unlike in Coman and Pancharevo, the decisions in Mirin and Cupriak-Trojan do not merely concern certain consequences of the relevant status. Instead, the requirement of cross-border validity is extended to the civil status itself: when a status is lawfully established in one Member State, it must be considered valid across the European Union.

Replication of Status: A Doctrine for PIL

If this development were to be translated into PIL doctrine, the term “replication of status”, in my view, better captures the specific structure than the umbrella term “recognition” or “principle of recognition”.

Replication of status means that a Member State must treat a civil status registered in another Member State as valid, provided that the status was lawfully registered under the standards applicable in the registering State. The requested State is not simply asked to accept the status registered in a foreign register. Rather, it must reproduce the status after inspecting (where necessary) whether the foreign registration was correctly made under the registering State’s rules. With this understanding, replication of status can serve as a doctrinal tool for addressing individual cases, potentially without recourse to autonomous conflict rules.

Three Necessary Distinctions

The term replication of status is meant to avoid terminological and conceptual blurring. Using the term can highlight three important distinctions.

First, replication of status — as a doctrine of PIL — should be distinguished from the “recognition principle” as a mandate of EU primary law. The Court of Justice derives its outcome requirements from the right to free movement. It sets limits of what results are permissible for Member States in a concrete case. It does not address how these results are to be reached. Replication of status, by contrast, can be understood as a PIL doctrine describing how those requirements can be operationalised within the structure of PIL. In other words: the primary-law recognition principle is the normative foundation; replication of status is a doctrinal method.

Second, replication of status is distinct from the referral method in PIL — the classic conflicts technique of designating an applicable law by the forum’s connecting factors. Under replication of status, the requested State does not undertake its own conflicts analysis based on its own conflict rules. Instead, the relevant benchmark for assessing the validity of the status is established by the registration in the first Member State and by the conflict rules applicable there. That is why the method is better described as “replication”, not as a mere variant of referral.

Third, replication of status must be distinguished from recognition of judgments, i.e. recognition in the sense of international civil procedure. A central hallmark of recognition of judgments is the general ban on a substantive review, i.e., the prohibition of a révision au fond. By contrast, replication of status allows for a substantive review: the requested State may verify whether the status was lawfully registered under the standards applicable in the registering Member State. Calling both phenomena “recognition” risks obscuring this crucial difference. A broad concept of recognition might be acceptable in the case law of the Court of Justice, which focuses on EU primary law. However, in the specific context of PIL, the term prevents terminological precision and conceptual clarity.

Why the Label Matters

One could, of course, describe the Court’s developing jurisprudence without introducing new terminology. However, a new method is clearly emerging from the case law, and I would submit that an independent method deserves its own name.

Replication of status is currently confined to registered civil status questions and, at least for now, is restricted to the status of Union citizens and status relationships between two Union citizens. It does not automatically settle everything that follows from that status. Hard questions remain about downstream effects for which the status constitutes a preliminary question. Those questions may still be addressed by ordinary PIL techniques, with replication of status operating as a decisive premise for status as a preliminary question.

At the same time, Mirin and Cupriak-Trojan make it harder to continue treating the requirements of the principle of recognition merely as an ex-post “correction” of domestic PIL outcomes. The requirements and legal consequences of the Court’s case law are now sufficiently concrete to discuss replication of status as an emerging doctrinal structure — one that may eventually invite legislative consolidation and possibly extension at the national or EU level.

Further Reading

A longer German discussion of these ideas is now available as a case note on Cupriak-Trojan: Konrad Duden, ‘Vom primärrechtlichen Anerkennungsprinzip zum Statusnachvollzug: Eine Dogmatik Jahrzehnte im Werden’ [2026] IPRax 178 (access to the full text depends on access to the database “juris”). The abstracts of the other contributions to the IPRax-issue can be found here.

A more extensive paper developing replication of status as a doctrine of PIL is forthcoming.