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Sincere cooperation meaning

Published by a LexisNexis EU Law expert
What does Sincere cooperation mean?
Sincere cooperation (often called loyal cooperation) describes, in practice, the EU law duty on Member States and EU institutions to work together to give effect to EU obligations and to avoid measures that could undermine EU objectives. It is set out in Article 4(3) TEU and developed by CJEU case law. Key features include: taking all appropriate national measures to implement and enforce EU law; facilitating Union tasks (such as information‑sharing and mutual assistance); and abstaining from steps that jeopardise EU policies. The duty binds all state organs, including courts, and underpins effective implementation of directives, recovery of unlawful State aid, cross‑border administrative and judicial cooperation, and the preliminary reference procedure. It cannot be used to expand EU competences beyond the Treaties. Breach is typically addressed via infringement proceedings or by national courts interpreting domestic law consistently with EU obligations. Jurisdictional position: - Ireland: fully applicable and routinely relied upon before Irish courts and the CJEU. - United Kingdom: post‑Brexit, the principle no longer binds the UK, save where specific instruments apply. The Withdrawal Agreement imposes a good‑faith obligation, and the Windsor Framework applies certain EU law in Northern Ireland, but the Article 4(3) TEU duty itself binds the EU and its Member States.
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NEWS
CJEU: Commission v Malta—Investor citizenship schemes breach EU law; Union nationality cannot be granted for payment; genuine link and actual residence required.

European Commission v Republic of Malta ECLI:EU:C:2025:283 What are the practical implications of this case? The judgment curbs Member States’ latitude in conferring nationality where this entails EU citizenship, and prohibits nationality—and thus EU citizenship—being awarded in return for fixed payments or investments. The court confirmed EU citizenship as a core status that demands a real connection between the applicant and the Member State. Granting nationality on the basis of finance alone would erode the substance of Union citizenship and violate the duty of sincere cooperation (Article 4(3) TEU). The ruling bolsters the Commission’s supervisory function, making clear it can contest naturalisation arrangements that impinge on EU citizenship rights. It underscores the court’s resolve to safeguard the integrity of EU membership and citizenship. Other Member States operating investor programmes to draw in foreign capital must rethink or scrap such citizenship offers, ensuring they are not commodifying nationality and thereby EU citizenship. The case also underscores the obligation to embed substantive integration measures in naturalisation routes, such as genuine...

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PRACTICE NOTES
Transposition of EU Directives: Member States’ obligations, implementation techniques, enforcement and direct effect, with archived guidance on pre‑Brexit UK practice

The transposition of EU Directives The transposition of EU Directives is the means by which Member States give legal effect to Directives within their own national systems. Unlike EU Treaty provisions and EU Regulations, which apply directly, Directives require domestic implementation, typically through primary or secondary legislation. They are the preferred legislative tool where national rules must be adjusted. Putting a Directive into national law ensures EU citizens can fully access the relevant rights and obligations. While Directives are binding as to the outcome, states remain free to select the form of implementation, but may not change the Directive’s substance. They must also implement within the specified deadline. The Council of the EU The Council together with the European Parliament The European Commission Obligation to transpose EU Directives Under Article 4(3) TEU, Member States owe a duty of loyal or sincere cooperation. Article 4(3) TEU guarantees the effectiveness of EU law within the Member States...

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PRACTICE NOTES
UK merger control: Court of Appeal upholds CMA order requiring Ryanair to cut Aer Lingus stake to 5%; issues of confidentiality, remedies and EU sincere cooperation

CASE HUB (appeal lodged by Ryanair at the Supreme Court; however, the Supreme Court refused permission to appeal) ARCHIVED – this archived case hub reflects the position at the date of the judgment of 12 February 2015; it is no longer maintained. See further, timeline, commentary and related cases. Case facts Outline Ryanair appealed the CAT’s decision endorsing the Competition Commission’s (CC) final report on its completed purchase of a minority holding in Aer Lingus, under which Ryanair was directed to cut its stake from 29.8% to 5%. The Court of Appeal handed down its judgment on 12/02/2015, dismissing the appeal... Parties Ryanair Holdings plc — Europe’s largest low-cost carrier, operating from 49 base airports across Europe; headquartered in Dublin, one of its biggest bases. Competition and Markets Authority (CMA) (formerly the Competition Commission) Aer Lingus Group plc (intervening) Background Ryanair obtained its 29.8% interest in Aer Lingus during 2006/07. It sought to acquire the remaining shares...

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