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Unfair Competition in France: How to Prove It and Take Action

Business

In the business world, competition is healthy and drives innovation, but it must be conducted in compliance with fair rules of play. When a competitor adopts dishonest practices to capture your clientele or harm your reputation, this is known as unfair competition. Faced with these actions, which can weaken or even destroy a business, French law offers powerful legal weapons to defend yourself, obtain compensation, and put an end to the disruption. This comprehensive guide, written by the experts at AvocatAI, explains how to identify unfair competition, how to gather evidence, and the steps to take to act effectively.

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What is Unfair Competition? The Substantive Rules

Unfair competition is not governed by a specific code, but is sanctioned under the general principles of civil liability. More precisely, *Article 1240 of the Code civil (French Civil Code) (formerly Article 1382) serves as the legal foundation: "Any human act whatsoever which causes damage to another commits him by whose fault it occurred to make reparation for it". In certain cases, notably when a contract binds the parties (such as a non-compete clause), Article 1231-1 of the Code civil*** relating to contractual liability applies instead.

For a competitor's liability to be engaged, case law requires the combination of three cumulative elements: a fault, damage (prejudice), and a causal link between the two.

The Four Main Types of Unfair Competition Faults

French case law has classified acts of unfair competition into four major categories:

1. *Disparagement (dénigrement):* This consists of publicly discrediting the products, services, prices, or reputation of a competitor. Even if the disclosed information is true, distributing it in bad faith to divert clientele constitutes a fault.

2. *Disorganisation (désorganisation):* This aims to disrupt the internal functioning of a competing business. It often manifests as the mass poaching of employees (aimed at stripping a team of its core substance), the theft of client files, or the misappropriation of trade secrets.

3. Imitation (or risk of confusion): This is the use of visual elements, logos, a trade name, a website, or packaging so similar to those of a competitor that the average consumer is misled and confuses the two businesses.

4. *Parasitism (parasitisme):* Unlike the other three, parasitism can exist even in the absence of a direct competitive relationship. It involves an economic actor riding on the coattails of another to benefit, without spending anything, from their investments, know-how, reputation, or research efforts.

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How to Prove Unfair Competition?

Under French business law, the burden of proof lies with the plaintiff, in accordance with *Article 9 of the Code de procédure civile (French Code of Civil Procedure)*. You must therefore prove your competitor's fault, your damage (loss of turnover, loss of opportunity, damage to image), and the causal link.

In commercial matters, evidence can be established by any means (preuve libre), but it must be obtained fairly. Here are the essential tools for building a solid case:

The Bailiff's Report (constat de commissaire de justice)

This is the gold standard of evidence. Whether it involves recording screenshots of a competitor's website plagiarising yours, disparaging posts on social media, or physical shop windows, a factual report (procès-verbal de constat) drawn up by a commissaire de justice (formerly known as a huissier de justice, a French judicial officer/bailiff) gives indisputable probative force to your evidence. For internet evidence, the bailiff must respect a strict technical standard (standard NF Z 67-147) for the report to be valid before a court.

The Order on Petition (ordonnance sur requête under Article 145 of the Code de procédure civile)

This is the secret weapon in unfair competition matters. If the evidence is located on your competitor's premises (stolen client files, disparaging emails, copied source codes) and you fear they might destroy it if you sue them openly, your lawyer can petition the President of the Tribunal de commerce (French Commercial Court) on the basis of *Article 145 of the Code de procédure civile***.

The judge can issue an ex parte order (without the competitor being notified in advance) authorising a commissaire de justice to enter the competitor's premises—accompanied if necessary by an IT expert and law enforcement—to copy files, seize documents, and retrieve emails containing specific keywords.

Testimonies, Written Statements, and Private Investigator Reports

You can produce written statements from clients (drafted in accordance with *Article 202 of the Code de procédure civile***) indicating that they were approached by the competitor using deceptive methods. Reports from a licensed private investigator are also admitted by the courts, provided that the tailing or surveillance does not disproportionately infringe upon the private life of the person being monitored.

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Practical Step-by-Step Actions to Take

If you are a victim of unfair competition, you must act methodically and swiftly. Here is the typical path to follow:

Step 1: Collect and Secure Evidence Immediately

Before taking any steps or contacting the competitor, secure your evidence. Have the necessary bailiff's reports (constats) carried out. If you suspect internal data theft by a former employee, have your IT systems audited by an expert.

Step 2: Send a Formal Demand Letter (mise en demeure)

Once the evidence is in your possession, have a lawyer draft a formal demand letter (mise en demeure). This letter, sent via registered mail with acknowledgment of receipt (lettre recommandée avec accusé de réception or LRAR), must list the grievances, reference the applicable legal statutes, and summon the competitor to:

Step 3: Attempt an Amicable Settlement or Mediation

If the competitor responds and is open to discussion, a negotiation phase can begin. This can lead to a settlement agreement (protocole d'accord transactionnel), which has the authority of a final judgment between the parties, providing for the cessation of the practices and the payment of a lump-sum compensation.

Step 4: Bring the Case Before the Competent Court

If the formal demand letter remains unsuccessful, you must initiate legal proceedings:

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Deadlines, Amounts, and Key Figures to Remember

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Concrete and Quantified Examples

To better understand how courts evaluate these situations, here are two case studies inspired by real French jurisprudence.

Example 1: Diversion of Clientele by a Former Employee

The situation: Thomas employs Julie as a sales representative in his communication consulting firm. Julie resigns to set up her own business. Upon leaving, she discreetly copies Thomas's client file (containing 150 qualified contacts). During the following 3 months, she actively pitches these clients, offering rates 20% lower. Thomas notices a sudden drop in his business.

The action and calculation of damages: Thomas instructs a bailiff who, via a court order, seizes Julie's professional computer and finds the stolen file as well as the solicitation emails. Thomas proves that he lost 12 long-standing clients to Julie, representing a loss of turnover of 80,000 €. Since his net margin on these contracts was 40%, his direct financial loss amounts to 32,000 € (80,000 € x 40%). The Tribunal de commerce orders Julie to pay 32,000 € in damages to Thomas for unfair competition through disorganisation, plus 3,000 € under Article 700 for legal costs.

Example 2: Parasitism of an E-commerce Site

The situation: The company "BioDélices" sells high-end organic fruit baskets online. It has invested 25,000 € in website design, graphic identity, and SEO. A competitor, "DélicesBio", launches by copying the exact structure of the website, the slogans, the product descriptions word-for-word, and by buying the brand name "BioDélices" on Google Ads to appear above the original.

The action and calculation of damages: BioDélices has an internet bailiff's report drawn up and petitions the summary judge. The judge orders the cessation of the Google Ads campaign and the modification of the website within 15 days, subject to a fine of 1,000 € per day of delay. On the merits, the court rules that DélicesBio saved research and creation costs by riding on the coattails of BioDélices. The court orders the plagiarist to pay 15,000 € for parasitism (calculated on the savings made on creation costs) and 8,000 € for damage to image and the confusion created among consumers.

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Mistakes to Avoid

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FAQ (Frequently Asked Questions)

Is it possible to sue for unfair competition if there is no written contract?

Yes, absolutely. An action for unfair competition is based on tortious liability (responsabilité délictuelle under Article 1240 of the Code civil). It does not require any prior contractual relationship between you and the offending competitor. It is the abnormal behavior contrary to honest commercial practices that is sanctioned.

What is the difference between infringement (contrefaçon) and unfair competition?

Infringement (contrefaçon) penalises the violation of a registered intellectual property right (a patent, a trademark registered with the INPI, a design). Unfair competition penalises faulty commercial behavior (parasitism, disparagement, confusion) that does not necessarily involve an intellectual property title. It is very common to combine both actions in the same lawsuit.

Can a former employee engage in unfair competition if they do not have a non-compete clause?

Yes. In the absence of a valid non-compete clause (clause de non-concurrence) in their employment contract, an employee regains their freedom to work or create a competing business (the principle of freedom of trade and industry). However, this freedom ends where dishonesty begins. If they use unfair methods (theft of files, disparagement of their former employer, mass diversion of clients before or just after their departure), they can be condemned for unfair competition.

How long does an unfair competition lawsuit take?

Before the Tribunal de commerce, a classic procedure on the merits takes on average between 12 and 18 months. If you use the emergency summary procedure (référé) to stop the actions, you can obtain an enforceable decision in 1 to 2 months.

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Summary

Legal information for guidance only, not personalised legal advice. For your specific situation, ask your question free of charge on AvocatAI — answers based on French law, in your language.

Content reviewed by the AvocatAI legal editorial team

This article is provided for information only and is not legal advice. Consult a lawyer for advice tailored to your situation.