The limits of judicial expertise in the face of algorithms: Google's trade secrets.

The Paris Court of Appeal has just rendered a major decision on September 13, 2024 (Paris Court of Appeal, Pôle 1 chambre 8, September 13, 2024, n° 24/01498) which clarifies the limits of judicial expertise when confronted with the algorithmic secrets of digital giants. To fully understand the scope of this decision, it is essential to explore the particular context of this case and its implications for the future of digital law.

A case revealing tensions between transparency and trade secrets.

At the heart of this case is a conflict between an online service provider for vehicle registration and Google.

This company, like many businesses today, relied heavily on Google Ads to acquire customers. After observing a significant increase in its advertising costs, it sought to understand the precise mechanisms that determine the price of its ads.

This request raises a fundamental question: how far can the right to evidence go in the face of a digital platform's trade secret? The company requested a thorough judicial expertise on the basis of Article 145 of the Code de procédure civile, aiming to analyze the algorithm that determines the quality of ads and influences their price.

Google Ads' mysterious \"Quality Score\".

To grasp the stakes of this decision \\ [1\")\\], one must understand how the Google Ads scoring system works. When an advertiser publishes an advertisement, Google assigns it a \" _Quality Score_\", a rating that influences both the ad's positioning and its cost.

This score is based on three main criteria:

- Expected click-through rate: Google estimates the likelihood that a user will click on the ad - Ad relevance to the user's search - Landing page experience: Google analyzes the quality of the website to which the ad points

While these criteria are public, their exact weighting and the algorithmic mechanisms that evaluate them remain confidential. It is precisely this 'trade secret' that the company wished to examine via judicial expertise.

A decision that draws clear boundaries.

The Court of Appeal lays down a fundamental principle: judicial expertise cannot disproportionately infringe on trade secrets, even when requested to preserve evidence.

It develops a three-step reasoning.

**Firstly**, it recognizes the legitimacy of Google's advertising auction system. It relies in particular on a decision by the Autorité de la concurrence \\ [2\\], which had validated this mechanism as relevant and effective for ad selection.

**Secondly**, it considers that Google fulfills its transparency obligations by communicating the general criteria for ad evaluation. Advertisers have sufficient information to understand the rules of the game, even if they do not have access to the technical details of the algorithm.

**Thirdly**, it considers that a detailed analysis of the algorithm would constitute a disproportionate infringement of Google's trade secrets. The algorithm represents the core of the company's added value and deserves particular protection.

A delicate balance between conflicting interests.

This decision illustrates the search for a delicate balance between several imperatives:

- Protection of innovation: digital platforms must be able to protect their algorithmic innovations, which often represent considerable investments.

- Necessary transparency: professional users of these platforms need sufficient information to conduct their business in an informed manner.

- Efficiency of justice: courts must be able to examine potentially litigious practices without compromising legitimate trade secrets.

Practical implications for digital players.

For digital platforms, this decision offers welcome protection for their algorithmic secrets. It sets a clear limit: while general criteria must be transparent, the precise scoring and ranking mechanisms can remain confidential.

For advertisers, the decision clarifies the extent of their right to information. They can demand communication of general rules and data relating to their own campaigns, but not access to the technical details of the algorithms.

For legal practitioners, the ruling provides a valuable analytical framework for the application of Article 145 of the Code de procédure civile in the face of trade secrets. It imposes rigorous proportionality control between the right to evidence and the protection of trade secrets.

A jurisprudence set to become a reference.

This decision establishes an important precedent for all litigation involving proprietary algorithms, whether for pricing, ranking, or content moderation.

It is part of a broader movement to regulate digital platforms, where the law must constantly adapt to reconcile technological innovation and the protection of user rights.

This balanced approach preserves both the innovation capacity of platforms and the legitimate rights of their professional users. It reminds us that algorithmic transparency can be ensured by communicating general operating principles, without necessarily requiring the disclosure of technical details.