Complaint to the CJEU – from A to Z: A Complete Step-by-Step Guide

A complaint to the CJEU is a key tool for protecting rights under EU law. It allows for challenging actions, omissions, or acts of EU institutions that violate EU law. In certain cases, it also enables private parties to pursue their rights before the Court of Justice of the European Union in Luxembourg. A complaint to the CJEU is a tool of great importance. It is crucial in institutional disputes between Member States and EU bodies. Moreover, it also helps individuals challenge acts that directly affect them.

This guide explains how to file a complaint with the CJEU. It covers the legal basis, admissibility rules, types of complaints, deadlines, formal requirements, common mistakes, practical tips, and the effects of CJEU rulings.

Table of Contents

What Is a Complaint to the CJEU?

A complaint to the CJEU (Court of Justice of the European Union) is a legal remedy that allows the challenge of acts, actions, or omissions of EU institutions, bodies, and agencies when they violate EU law. The CJEU examines complaints submitted by Member States. Under certain conditions, it may also review complaints of natural and legal persons.

A complaint to the CJEU is a key mechanism for reviewing the legality of actions taken by EU institutions. It serves as a guarantee that EU law is respected throughout the Union. You can find more information about the work of the CJEU here.

Types of Complaints Examined by the CJEU

The most common types include:

Action for annulment of an act (Article 263 TFEU)
Action for failure to act (Article 265 TFEU)
Action for damages against the EU (Articles 268 and 340 TFEU)
Action against a Member State for infringement of EU law (Articles 258–260 TFEU)
Appeals against judgments of the General Court

Each type of complaint is governed by different rules, deadlines, and admissibility criteria. Understanding them is essential for conducting effective proceedings.

Who Can File a Complaint with the CJEU?

1. Member States

They may challenge acts of EU institutions or file complaints against other Member States. Although in practice, the latter mechanism is used rarely.

2. EU Institutions

The European Parliament, the Council, and the Commission use this right for institutional purposes. For example, in competence-related disputes.

3. Natural and Legal Persons (Individual Complaint)

An individual or a legal entity may file a complaint only in two situations:

the EU act concerns them directly and individually, or
they challenge a regulatory act that concerns them directly and does not require executive measures.

Examples of acts that may be subject to a complaint:

a Commission decision imposing a fine on a company;
refusal to register an EU trademark;
a decision of an EU body concerning a specific business (e.g., EASA, EMA).

Legal Basis for a Complaint to the CJEU

Filing complaints with the CJEU is based on the provisions of the primary law of the European Union. The most important regulations include:

Treaty on the Functioning of the European Union (TFEU) – Articles 258–260, 263–265, 268, and 340
Treaty on European Union (TEU)
Statute of the Court of Justice of the European Union
Rules of Procedure of the CJEU

Depending on the type of complaint, the legal basis may also include sector-specific acts. For example, regulations concerning data protection (GDPR), the energy market, or air transport.

Complaint to the CJEU – When Can You File It?

1. Action for Annulment (Article 263 TFEU)

It may be filed if an EU act violates:

EU substantive law;
procedural rules;
the principles of proportionality or subsidiarity;
fundamental rights.

The act must be final and produce legal effects for the complainant.

2. Action for Failure to Act (Article 265 TFEU)

This applies when an EU institution was obliged to take action (e.g., issue a decision) but failed to do so.

3. Action Against a Member State (Articles 258–260 TFEU)

Brought mainly by the European Commission. It concerns breaches of EU law by a Member State—for example, failure to implement a directive.

4. Action for Damages Against the EU

This may be brought if the actions of EU bodies caused financial loss.

Deadlines for Filing a Complaint with the CJEU

The deadline depends on the type of complaint:

Action for annulment – 2 months from the publication of the act, its notification to the complainant, or its announcement.
Action for failure to act – the institution must first be called upon to act. If it does not respond within 2 months, a complaint may be filed.
Action for damages – no strictly fixed deadline, but the principle of due diligence applies.

Errors in calculating deadlines often lead to the complaint being rejected as inadmissible.

Complaint to the CJEU – Step-by-Step Procedure

1. Analysis of the admissibility of the complaint

This is the most important stage. Errors in the assessment of admissibility are the most common reason for rejection. It should be determined:

whether a complaint is available in the given situation;
whether the applicant has legal standing;
whether there is a legal interest;
whether the deadline has been met.

2. Preparation of the content of the complaint

A complaint to the CJEU must include:

identification of the parties;
specification of the subject matter of the complaint;
the allegations and their justification;
evidence;
the final request (e.g., annulment of an act)

The formal requirements are strict. The complaint must not contain deficiencies that make it difficult to examine.

3. Filing the complaint via the e-Curia system

Complaints are submitted only electronically, via the e-Curia platform. This requires you to create an account and confirm your identity.

4. Proceedings before the CJEU

The Court may:

request additional documents;
hear the parties;
allow the intervention of other participants;
schedule a court hearing.

5. Judgment

The CJEU may:

uphold the complaint;
dismiss it;
discontinue the proceedings.

The judgment is final and binding.

Effects of a Successful Complaint to the CJEU

Action for annulment

If the Court upholds the action:

the contested act is repealed;
the effects of the annulment may be limited in time (if required for legal certainty).

Action for failure to act

The CJEU finds and identifies a violation, and the institution is obliged to take action.

Action for damages

If the complaint is upheld, the CJEU awards damages to the applicant.

Most Common Mistakes When Filing a Complaint with the CJEU

incorrect assessment of whether the act affects the complainant directly and individually;
filing a complaint after the deadline;
incorrect formulation of the allegations;
failure to indicate how EU law has been violated;
relying on insufficient evidence;
formal errors (e.g. lack of an electronic signature in e-Curia).

Examples of Situations Where Filing a Complaint to the CJEU Is Worth Considering

refusal to register an EU trade mark;
a penalty imposed by the European Commission;
a decision of an EU authority that violates competition rules;
an EU act directly affecting the situation of the entrepreneur;
lack of action by an EU institution despite a legal obligation (e.g., delay in an administrative procedure before the Commission).

Complaint to the CJEU – Summary

A complaint to the CJEU is one of the most important instruments for controlling the functioning of EU institutions. It is a way to enforce the rights of individuals within the EU order. The procedure is formalised and requires precise preparation of evidence and knowledge of the Treaty provisions. Yet, it is an effective way to assert one’s rights in cases where the actions of the EU institutions violate the law.

Get professional help. If you are considering filing a complaint with the CJEU, need an analysis of the admissibility of a complaint or want to assess whether an EU act affects you directly and individually, contact us. We help in the preparation of complaints, represent clients before the CJEU and conduct a full analysis of litigation risk. Use professional legal services to increase your chances of defending your rights before the Court.

FAQ – Questions and Answers About Filing a Complaint with the CJEU

1. Can an individual file a complaint with the CJEU on their own?

Yes, but only in strictly defined cases. An individual may file a complaint if an EU act affects them directly and individually, or if it is a regulatory act that does not require effective measures. In practice, meeting these conditions can be difficult and requires a legal analysis.

2. How much does it cost to file a complaint with the CJEU?

The Court does not charge a court fee for bringing an action. The costs mainly concern the attorney’s remuneration and the costs of preparing documents. In economic matters, these costs can be high. It is advisable to assess cost-effectiveness in advance.

3. How long do CJEU proceedings take?

Usually from 18 to 30 months. Particularly complicated cases may take longer. The Court may also apply an expedited procedure if required by the public interest or important interests of the parties.

4. Do entrepreneurs often use complaints to the CJEU?

Yes, especially in cases related to decisions of the European Commission. For example, antitrust, refusal to register trademarks, or acts preventing business activity. It is an effective tool for protection in disputes with EU institutions.

5. Can I make a complaint if an EU institution does not reply to a request or letter?

Yes. In such a case, an action for failure to act may be filed — but only after the institution has first been formally called upon to act.