Trade secrets and the right to evidence: what balance?

Trade secrets take precedence over the right to evidence if the latter is not essential. In a case between Domino’s Pizza and Speed ​​Rabbit Pizza, the Paris Court of Appeal strictly applied the principle of proportionality, penalizing the production of a confidential document deemed non-essential to the defense.

A recap of the facts and the procedure: a legal saga

This decision is part of a long-standing dispute between two giants of the takeaway pizza industry, illustrating the tensions between the protection of strategic information and the need for evidence in competition matters.

An accusation of unfair competition within a network

At the heart of the dispute, Agora, a former franchisee of the Speed ​​Rabbit Pizza (SRP) network, sued Domino’s Pizza France (DPF) in 2012 for acts of unfair competition.

The Production of a Controversial Document: The “OER Guide”

To support its accusations, Agora, joined by its former franchisor SRP, produced an internal Domino’s Pizza document in court: the “2018 OER Guide.”

After several rulings and two appeals, the Court of Cassation, in a judgment dated June 5, 2024, referred the case back to the Paris Court of Appeal. The central question before the referral court was whether the production of this document was essential to proving the acts of unfair competition and whether the infringement of trade secrets was strictly proportionate to this objective.

The Reflection of a Major Jurisprudential Development

This judgment perfectly illustrates the recent and significant evolution of case law regarding the admissibility of evidence obtained illegally or unfairly.

Before 2023: Fair Evidence as a Cardinal Principle

Traditionally, in civil and commercial matters, the Court of Cassation established a strict principle: evidence obtained unfairly was inadmissible. Unlike criminal matters, where evidence is freely admissible, civil proceedings were governed by an imperative of fairness. Any evidence obtained unfairly—that is, through manipulation, trickery, or in violation of a right (respect for privacy, confidentiality of correspondence, etc.)—was systematically deemed inadmissible and therefore excluded from the proceedings, without the judge having to assess its relevance or necessity. Case law, however, distinguished between unfair evidence, deemed inadmissible, and illegal evidence, which could be declared admissible when such evidence was essential to the success of the claim of the party relying on it and when the infringement of the conflicting rights was strictly proportionate to the objective pursued.

The Plenary Assembly’s Reversal of December 22, 2023

In a highly anticipated landmark ruling of December 22, 2023, the Plenary Assembly of the Court of Cassation (Cass. com., Dec. 22, 2023, No. 20-20.648) made a major reversal by aligning itself with the case law of the European Court of Human Rights. It ruled that, even in civil matters, evidence obtained both unlawfully and unfairly—the two scenarios being potentially difficult to distinguish—is no longer automatically inadmissible.

From now on, the judge must weigh the competing interests:

1. It must be essential to the exercise of the right to evidence;
2. The infringement of the opposing party’s rights must be strictly proportionate to the objective pursued.

The Rigorous Application of the Proportionality Test Now Required

In its judgment of October 8, 2025, the Paris Court of Appeal conducted a meticulous two-step analysis, applying the principles recently established by the case law of the Court of Cassation.

Confirmation of the Trade Secret Classification

The court first confirmed that the “OER Guide” is indeed protected as a trade secret. To this end, it verified the three cumulative criteria of Article L. 151-1 of the French Commercial Code:

1. The information is not generally known or readily accessible: The guide contains very precise information on Domino’s Pizza’s specific standards, constituting “distinctive and secret know-how”;
2. The information has commercial value: Due to its confidential nature, this guide, which aims to improve the profitability of points of sale, possesses actual or potential commercial value;
3. The information is subject to reasonable safeguards: The guide bore a statement on each page indicating its “strictly confidential” nature and prohibited any disclosure, which the court deemed a sufficient safeguard.

Having established the classification of the trade secret, the court concluded that its acquisition and production by a competitor, without the consent of its owner, were unlawful.

The proportionality test: evidence neither essential nor proportionate

This is the crux of the decision. The court weighs the right to the protection of trade secrets against the right to evidence.

• On the essential nature of the evidence: The court ruled that producing the guide was not essential to the exercise of SRP and Agora’s right to evidence, particularly because the dispute concerned the granting of payment extensions that violated applicable legal provisions, whereas the guide did not address this issue;
• On the proportionate nature of the infringement: The court considered that the infringement of Domino’s Pizza’s trade secret was not strictly proportionate to the objective pursued:
  • The link between the document and the alleged facts is “very tenuous”;
  • Only two paragraphs of a 23-page document were cited as relevant, but the document was produced in its entirety;
  • Numerous other, non-confidential documents had already been produced to prove the same facts.

Consequently, the court dismissed the objection regarding the right to evidence and upheld the breach of trade secrets. It ordered in solidum SRP and Agora jointly and severally to pay €30,000 to DPF in compensation for moral damages, as DPF was unable to quantify any commercial harm

The Domino’s Pizza ruling: a concrete illustration of the new paradigm

The ruling of October 8, 2025, is one of the first notable applications of this new proportionality test in matters of trade secrets. It demonstrates that while the door is now open to the production of illicit or unfair evidence, the conditions remain extremely strict.

The Court of Appeal does not simply acknowledge the usefulness of the evidence; it verifies its “indispensability.” By noting that the plaintiffs had alternative means of proof, the court ruled out the admissibility of the “OER Guide.”

For practitioners of distribution and network law, this decision sends a strong signal: the protection of trade secrets, enshrined in the Commercial Code in 2018, remains robust. A competitor or former partner can only seize confidential documents and hope to use them in court if this evidence is the sole means of asserting their rights, which, in practice, will rarely be the case. The ruling confirms that the right to evidence is not a blank check to justify the violation of trade secrets.