Opinion of the Advocate General — ECLI:EU:C:2024:130
Date: 2024-02-08
Language of the case: German
Subject matter: Area of freedom, security and justice;Judicial cooperation in civil matters
Procedure: Reference for a preliminary ruling
Origin: Germany

summary of the course of proceedings] 
ruled as follows on 16 January 2023: 
I. 
The proceedings are stayed. 
II. 
The following questions are referred to the Court of Justice of the European Union 
(‘CJEU’) for a preliminary ruling on the interpretation of Articles 10 and 11 of 
Council Regulation (EC) No 2201/2003 of 27 November 2003 concerning 
jurisdiction and the recognition and enforcement of judgments in matrimonial 
matters and the matters of parental responsibility, repealing Regulation (EC) 
No 1347/2000 (‘Brussels IIa Regulation’): 
To what extent is the regulatory mechanism provided for in Article 10 and 
Article 11 of the Brussels IIa Regulation limited to proceedings conducted in the 
context of relations between EU Member States? 
More specifically: 
1. Does Article 10 of the Brussels IIa Regulation apply, with the effect that the 
jurisdiction of the courts in the former State of residence is retained, if the child 
had his or her habitual residence in an EU Member State (Germany) before his or 
her removal and the return proceedings under the Hague Convention on the Civil 
Aspects of International Child Abduction (‘the HCAC’) were conducted between 
an EU Member State (Poland) and a third State (Switzerland) and, in those 
proceedings, the return of the child was refused? 
If question 1 is answered in the affirmative: 
2. In the context of Article 10(b)(i) of the Brussels IIa Regulation, what 
requirements are to be imposed for the purposes of establishing continuing 
jurisdiction? 
3. Does Article 11 (6) to (8) of the Brussels IIa Regulation also apply in the 
case of return proceedings implemented under the HCAC in the context of 
relations between a third State and an EU Member State, as a State of refuge, in so 
far as the child had his or her habitual residence in another EU member state 
before the removal? 
GREISLZEL 
 
3 
Grounds: 
I. 
The proceedings concern questions relating to the scope of application of 
Articles 10 and 11 of the Brussels IIa Regulation. 
The child’s parents were married in Frankfurt am Main on 7 March 2013. The 
father has German nationality and the mother has Polish nationality. The child’s 
parents initially lived together in Frankfurt am Main (Germany). On 29 June 2013, 
the father relocated to Switzerland for professional reasons. 
Their common child, L, of German nationality and now subsequently acquired 
Polish nationality, was born on 12 November 2014 in X (Switzerland) and lived 
with the mother in Frankfurt am Main from January 2015 until early April 2016. 
The father regularly visited the mother and child in Germany, and they also spent 
holidays together. On 11 May 2015, the Migration Office approved the father’s 
application for family reunification. The mother was granted a temporary 
residence permit for Switzerland, which was valid until 31 December 2019. 
On 9 April 2016, the mother moved to Poland with L. In doing so, the mother 
deregistered the entire family from the population register in Frankfurt, providing 
the father’s address in Switzerland. In the summer of 2016, the mother applied for 
jobs in Switzerland. Since November 2016, the mother has been working in 
Poland for Zurich Insurance. 
Initially, the father made visits to Poland. As of 17 April 2017, the mother refused 
the father access to their common daughter and enrolled their daughter in a 
kindergarten in Poland without the consent of the father. In late May 2017, the 
mother informed the father that she intended to remain in Poland with their 
daughter. 
By application of 7 July 2017, the father applied via the Swiss Central Authority 
(Federal Office of Justice in Bern) for the return of the child to Switzerland. By 
decision of 8 December 2017, the Sąd Rejonowy dla Krakowa-Nowej Huty w 
Krakowie (District Court for Krakow-Nowa Huta in Krakow, Poland) rejected 
that application on the ground that the father had given indefinite consent for the 
mother’s move to Poland with L. In addition, the court affirmed that there was a 
grave risk to the best interests of the child in the event of her return as 
contemplated in point (b) of the first paragraph of Article 13 of the HCAC. The 
father had admitted to the (one-time) use of force against the mother. The father’s 
appeal against that decision was dismissed by decision of the Sąd Okręgowy w 
Krakowie (Regional Court in Krakow, Poland) dated 17 April 2018 (XII Ca 
168/18). 
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By application of 27 September 2017, the mother initiated divorce proceedings in 
Poland. In October 2017, the mother deregistered L from the residents’ register of 
the municipality X in Switzerland. 
By decision of 5 June 2018, the Regional Court in Krakow provisionally entrusted 
the mother with parental custody of the common child and set the father's 
maintenance obligation. 
The father did not continue to pursue an application that was lodged with the 
German Federal Office of Justice in Bonn on 29 June 2018, which sought the 
return of the child on the basis of the HCAC. 
In the present proceedings, the father applied, under point I of an application dated 
12 July 2018, which was lodged with the Amtsgericht Frankfurt am Main (Local 
Court in Frankfurt am Main, Germany) on 13 July 2018, for the transfer of sole 
parental custody of the child and, in the alternative, for the right to determine the 
place of residence. 
Under point II of that application, the father also requested that the mother be 
ordered to return the child to the father in Switzerland as of the effective date of 
the decision. 
The father submitted that, in the spring of 2015, the child’s parents had agreed that 
they would continue to live with L in Switzerland in the future. In April 2016, the 
mother had decided to join her parents in Poland for a temporary period in order 
to assist them in building a house. The father had allegedly agreed to this but had 
expressly limited the period to two years, or three years at the maximum. In any 
case, it was allegedly agreed that the child was to attend kindergarten in 
Switzerland as of November 2017 at the latest. 
The mother opposed the application. 
The mother claims that the father consented to the move to Poland and provided 
assistance there in the process of obtaining a Polish passport. According to the 
mother’s submissions, there had been no agreement on a time limited move to 
Poland, just as there had been no agreement on a move to Switzerland. 
At first instance, the father was heard on 9 May 2019. The mother, who had also 
been summoned and had, by letter of 19 April 2019, requested the hearing 
beforehand by means of mutual legal assistance procedures, did not appear at that 
hearing. 
During that hearing, the father stated that the parents had, in a telephone 
conversation held on 29 January 2016, discussed the issue that L was to stay in 
Poland for a maximum period of two to three years and was, in any event, to 
attend kindergarten in Switzerland. 
GREISLZEL 
 
5 
By decision of 3 June 2019, notified on 7 June 2019, the Local Court dismissed 
the father's application for the transfer of parental custody. 
In its reasoning, that court stated that the court seised lacked international 
jurisdiction. The father had failed to demonstrate that a suitably specific 
agreement had been made to the effect that the mother and child would reside in 
Poland on a time limited basis. His statements during the oral arguments on 9 May 
2019 had contradicted his earlier submission contained in the written statement of 
3 August 2018, from which it was apparent that, in May 2017, the parents were 
still engaged in open-ended communications concerning the duration of the stay in 
Poland. 
The father considers that the Local Court in Frankfurt am Main has jurisdiction on 
the basis of Article 11(6), read in conjunction with Article 11(7), of the Brussels 
IIa Regulation, as well as on the basis of Article 10 of the Brussels IIa Regulation. 
In its decision of 8 December 2017, the District Court in Krakow found that the 
child had not had her place of residence in Switzerland prior to being resident in 
Poland because the child had been living with the mother in Germany. 
The father is of the opinion that the principles applicable in the HCAC 
proceedings – according to which the person opposing the return of the child must 
prove that the person having the (joint) care of the person of the child had 
consented to or subsequently acquiesced in the removal or retention – apply also 
in the present proceedings. According to the father’s submissions, the mother has 
not provided proof of consent for an unlimited period. 
With respect to the substance of the case, the father further submits that a transfer 
of parental custody to the father would be in the best interests of the child. By 
acting unilaterally, the mother had effectively overridden the powers of the father, 
who held rights of custody, and had therefore not acted in the best interests of the 
child. In that regard also, the father refers to the principles applicable to HCAC 
proceedings. 
By his appeal lodged with the Local Court on 8 July 2019, the father is continuing 
to pursue the application he made at first instance. 
The mother requests that the appeal be dismissed. 
The Chamber has repeatedly informed the father that his appeal lacks any prospect 
of success; this is because, even if it were to be assumed that the court had 
international jurisdiction, it could not be assumed that transferring parental 
custody to the father would be most conducive to the best interests of the child; 
Paragraph 1671 of the Bürgerliches Gesetzbuch (German Civil Code, ‘the BGB’). 
Similarly, the Chamber drew the father’s attention to the fact that, in the opinion 
of the Chamber, the application of Article 10 of the Brussels IIa Regulation is 
restricted to relations between EU Member States and that proceedings conducted 
REQUEST FOR A PRELIMINARY RULING OF 16. 1. 2023 – CASE C-35/23 
 
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between Poland and Switzerland cannot trigger the effects of Article 10 of the 
Brussels IIa Regulation. 
The father proposes that, in the context of preliminary ruling proceedings, the 
following questions be referred to the Court of Justice of the European Union in 
Luxembourg for a preliminary ruling: 
[…] 
[Questions for which the father proposes that clarification be sought. Partially 
included in the questions actually referred for a preliminary ruling, which are the 
only relevant questions] 
In 2022, the father had contact with the child in Poland on the basis of a court 
order issued in that country. 
II. 
1. International jurisdiction 
As a general rule, the international jurisdiction of the German courts to hear 
parental custody proceedings initiated before 1 August 2022 stems from 
Article 8(1) of Council Regulation (EC) No 2201/2003 of 27 November 2003 
(‘the Brussels IIa Regulation’), unless priority rules laid down in Articles 9, 10 
and 12 apply (Article 8(2) of the Brussels IIa Regulation). The successor 
regulation, Regulation (EU) 2019/1111 of 25 June 2019 (‘the Brussels IIb 
Regulation’), applies only to proceedings initiated after 1 August 2022; [Article] 
100(1) of the Brussels IIb Regulation. In the present proceedings, the Brussels IIa 
Regulation, in the version of Regulation (EC) No 2201/2003, continues to apply; 
Article 100(2) of the Brussels IIb Regulation. 
According to Article 8(1) of the Brussels IIa Regulation, the relevant connecting 
factor for a finding of international jurisdiction is the place where the child is 
habitually resident (a), unless any priority provisions apply; in this case, Article 10 
of the Brussels IIa Regulation (b.). 
a. Article 8(1) of the Brussels IIa Regulation 
According to Article 8(1) of the Brussels IIa Regulation, the courts of a Member 
State are to have jurisdiction in matters of parental responsibility over a child who 
is habitually resident in that Member State at the time the court is seised. 
Habitual residence is to be determined taking account of all the circumstances of 
fact specific to each individual case reflecting the integration of the child in a 
social and family environment as a centre of the child’s life and existence; in this 
respect the duration, regularity and conditions of the stay on the territory of a State 
are relevant factors (CJEU, judgments of 2 April 2009, (C-523/07, paragraphs 42 
GREISLZEL 
 
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and 44); of 22 December 2010, (C-497/10 PPU, paragraph 47); and of 8 June 
2017, (C-111/17 PPU, paragraph 42). 
L has lived in Poland with her mother since April 2016 and attended a daycare 
centre there since April/May 2017. 
At the time when the application was lodged, in July 2018, L had established her 
habitual residence in Poland, which means that the German courts cannot have 
jurisdiction on the basis of Article 8(1) of the Brussels IIa Regulation. 
b. Jurisdiction in cases of child abduction 
Article 10 of the Brussels IIa Regulation contains a more extensive jurisdiction 
provision for cases of wrongful removal or retention of a child. In such cases, the 
international jurisdiction of the State of former habitual residence is retained, even 
if the child establishes a new habitual residence in another State, unless specific 
conditions are met. 
In this respect, the scope of application of Article 10 of the Brussels IIa 
Regulation would first have to be established in the present proceedings. 
According to the wording of Article 10 of the Brussels IIa Regulation (‘Member 
State’), application of the provision is limited to relations between Member States 
bound by the Brussels IIa Regulation. In this regard, the CJEU has clarified that 
the fact that Article 10 of the Brussels IIa Regulation uses the expression 
‘Member State’ and not the words ‘State’ or ‘third State’, and that it provides that 
the conferral of jurisdiction is subject to current or previous habitual residence ‘in 
a Member State’, while making no reference to the possibility of a residence being 
acquired in the territory of a third State, also implies that that article deals solely 
with jurisdiction in cases of child abductions from one Member State to another 
(CJEU, judgment of 24 March 2021, C-603/20 PPU, paragraphs 38-40). 
The father considers that this condition is fulfilled since the present proceedings 
are being conducted in the context of relations between Germany and Poland and 
thus between two EU Member States bound by the Brussels IIa Regulation. L 
lived with her mother in Frankfurt and thus had her habitual residence in 
Germany. 
The Chamber does not share this view; instead, it regards the application of 
Article 10 and Article 11 of the Brussels IIa Regulation in the context of 
implementation of a return procedure under the HCAC. Article 11 of the Brussels 
IIa Regulation contains additional procedural rules that apply in return 
proceedings under the HCAC, where both the State of origin and the State of 
refuge are EU Member States or are bound by the Brussels IIa Regulation 
[…][reference to legal literature]. Whereas, on the one hand, the provisions 
contained in Article 10 and Article 11 of the Brussels IIa Regulation bolster the 
return mechanism provided for under the HCAC by limiting the scope of 
application of the exceptions and favouring the enforcement of a return order, 
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there are, on the other hand, special expediting provisions and provisions 
governing hearings, as well as protection and information requirements vis-à-vis 
the parties involved. 
In its judgment of 24 March 2021, C-603/20 PPU, on the interpretation of 
Article 10 of Regulation (EC) No 2201/2003 (here: determination of residency in 
cases of child abduction), the CJEU stated that in interpreting a provision of EU 
law, it is necessary to consider not only its wording, but also the context in which 
it occurs and the objectives pursued by the rules (CJEU, judgment of 24 March 
2021, C-603/20 PPU, paragraph 37). Accordingly, as regards the interpretation of 
Article 10 of the Brussels IIa Regulation, it follows clearly from the wording of 
that provision and from the interpretation set out in the Practice Guide for the 
application of Regulation No 2201/2003, published by the European Commission, 
that the rule concerns only conflicts of jurisdiction between Member States and 
not those between a Member State and a third State (CJEU, judgment of 24 March 
2021, C-603/20 PPU, paragraph 29). At the same time, the CJEU emphasised that 
special grounds of jurisdiction are to be interpreted restrictively and cannot, 
therefore, give rise to an interpretation that goes beyond the situations expressly 
envisaged by the regulation concerned, or which results in only one part of its 
wording being taken into account so as to apply that part independently(CJEU, 
judgment of 24 March 2021, C-603/20 PPU, paragraphs 47 and 48). 
Accordingly, it is the Chamber’s understanding that Articles 10 and 11 of the 
Brussels IIa Regulation are not to be considered in isolation from each other. 
In the return proceedings initiated at the father’s request of 7 July 2017 via the 
Federal Office of Justice in Bern, which sought the return of the child to 
Switzerland, the requirements under Article 11 of the Brussels IIa Regulation 
governing the conduct of HCAC proceedings were not applied because 
Switzerland is not bound by the Brussels IIa Regulation. Accordingly, following 
the rejection of the application for return, the court in Poland also had no reason to 
act in accordance with Article 11(6) and (7) of the Brussels IIa Regulation and 
thus inform the courts or central authority in Germany of the order on non-return. 
The second application for return, which the father lodged with the German 
Federal Office of Justice in Bonn shortly before the initiation of the present 
proceedings, cannot form the basis for continuity of jurisdiction under Article 10 
of the Brussels IIa Regulation because those proceedings are not being pursued. It 
is the receipt of an application by a court that is decisive in that regard. According 
to the father’s statements, no further return proceedings have been initiated in 
Poland. 
Moreover, the admissibility of a second HCAC application appears doubtful in 
principle, since the final decision of the court of appeal in Poland is likely to 
preclude the initiation of further HCAC proceedings on the same subject matter. 
The decisions of the Polish courts also contain remarks on the issue of the 
wrongful retention of the child. 
GREISLZEL 
 
9 
2. Application of Article 10 of the Brussels IIa Regulation 
If, in principle, Article 10 of the Brussels IIa Regulation applies also to the 
situation at issue in the present case, a change of jurisdiction (in the absence of 
acquiescence by both holders of rights of custody, point (a)) occurs only when the 
child has acquired a new habitual residence, has resided in the new State of 
residence for a period of at least one year, has settled in his or her new 
environment, and at least one of the situations referred to under point (b) (i) – (iv) 
has been met. Point (i) is at issue in the instant case; according to that provision, 
continued jurisdiction ceases if, within one year after the holder of rights of 
custody has had or should have had knowledge of the whereabouts of the child, no 
request for return has been lodged before the competent authorities of the Member 
State where the child has been removed or is being wrongfully retained 
(Article 10(b)(i) of the Brussels IIa Regulation). 
Accordingly, the father had to lodge the application for return within one year of 
acquiring knowledge, or of occurrence of the wrongful situation, in order for the 
international jurisdiction of the local courts to be maintained. 
The father claims that he consented to the mother residing with L in Poland on a 
time limited basis. After the expiry of that time limit, the mother had not moved to 
Switzerland with L, contrary to the agreement alleged by the father. 
In this regard the father submits that the child has been wrongfully retained in 
Poland since 24 May 2017 at the latest (attendance at a daycare centre). The father 
also maintains that the parents had made an agreement that the child was to attend 
a daycare centre in Switzerland as of November 2017. 
The father’s application for custody was lodged with the Local Court on 13 July 
2018. The one-year time limit laid down in Article 10(b) (i) of the Brussels IIa 
Regulation would be complied with only if the later date – that is to say, the date 
of admittance to the daycare facility – were to be applied. On the basis of the 
submission lodged in the return proceedings (occurrence of the wrongful situation 
upon enrolment at a daycare centre as of May 2017), the application was not 
received within the one-year time limit laid down in Article 10(b) (i) of the 
Brussels IIa Regulation. 
The question at issue here is whether the father is precluded from making further 
submissions as a result of the HCAC proceedings being conducted in Poland or if, 
in the context of Article 10 of the Brussels IIa Regulation, later start dates may 
also be applied. This would mean that, upon conclusion of the return proceedings, 
it would be possible to delay the start date for commencement of the one-year 
time limit, which is ultimately inconsistent with the intention of obtaining a 
prompt clarification of the rights of custody in line with the best interests of the 
child. 
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Furthermore, the parents disagree on the question of whether the mother’s stay in 
Poland with the child had been subject to a time limit. The mother denies that such 
a time limit had been agreed upon. 
With respect to the question concerning the requirement to state the case and the 
burden of proof, the father refers to the principles applicable to the proof of 
consent or agreement in HCAC proceedings, according to which the parent who 
opposes the return must establish that the applicant consented to or (subsequently) 
acquiesced in the removal (see Article 13(1)(a) of the HCAC). 
In the Chamber’s opinion, the special rules governing the burden of proof that 
apply in HCAC proceedings cannot be transposed to the present proceedings. The 
present proceedings do not concern the return of the child in the context of HCAC 
proceedings, but rather a transfer of parental custody, which is subject to the 
principles of procedural law that are generally applicable to custody proceedings. 
The conditions laid down in Article 10 of the Brussels IIa Regulation must be 
examined independently by the courts in the former State of residence (CJEU, 
judgment of 22 December 2010, Case C-497/10 PPU, paragraphs 62 et seq.). They 
are not bound by the decision handed down in the new State of residence on the 
application for return under the HCAC. In this respect, the principle of ex officio 
inquiry set forth under Paragraph 26 of the Gesetz über das Verfahren in 
Familiensachen und in den Angelegenheiten der freiwilligen Gerichtsbarkeit (Act 
on Proceedings in Family Matters and in Matters of Non-contentious Jurisdiction) 
applies, which also requires that the international jurisdiction is to be examined ex 
officio (Bundesgerichtshof (Federal Court of Justice (Germany) […] [reference to 
legal journal] [Decision 17 February 2010 – XII ZB 68/09]). In that regard, in the 
context of application proceedings such as the present application for transfer of 
parental custody pursuant to Paragraph 1671 of the BGB, the parties are subject to 
a certain requirement to substantiate the facts that are favourable to them. Thus, 
contradictions in the father's submission must also be assessed accordingly by the 
court. 
3. Application of Article 11(8) of the Brussels IIa Regulation 
In the event that an order of non-return of the child is issued in the HCAC 
proceedings on the basis of Article 13 of the HCAC, the provisions laid down in 
Article 11 (6) to (8) of the Brussels IIa Regulation provide that custody 
proceedings are to be initiated in the former State of residence. In particular, 
parental custody decisions falling within the scope of application of Article 11 of 
the Brussels IIa Regulation that are rendered following an order of non-return of 
the child in HCAC proceedings, and which include the surrender (return) of the 
child, are subject to privileged enforcement in accordance with Article 11(8) of 
the Brussels IIa Regulation and Article 40(1)(b), read in conjunction with 
Article 42 of the Brussels IIa Regulation. 
GREISLZEL 
 
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The father considers that a decision of the Chamber on parental custody that is 
associated with an order for the return of the child is subject to Article 11(8) of the 
Brussels IIa Regulation and hence to the rules on privileged enforcement. 
However, in the opinion of the Senate, the application of Article 10 (6) to (8) of 
the Brussels IIa Regulation necessarily presupposes that HCAC proceedings have 
been conducted in the context of relations between two Member States bound by 
the Brussels IIa Regulation, which means that Article 11(8) of the Brussels IIa 
Regulation would not apply in the present case. The purpose of Article 11(8) of 
the Brussels IIa Regulation is to facilitate the enforcement of custody decisions 
rendered following HCAC proceedings that are subject to the specific 
requirements laid down in Article 11 (2) to (5) of the Brussels IIa Regulation. As 
previously explained, the return proceedings conducted in the context of relations 
between Switzerland and Poland did not fall within the scope of application of the 
Brussels IIa Regulation. In this respect, the decisive factor is not the father’s place 
of residence but the question of the mutual commitments and obligations of the 
States under the Brussels IIa Regulation. 
[…] 
[…] 
[Signatures; certification as a true copy]