The mod: a creation under constraints

For some twenty years, it has been hard to avoid, on YouTube, those compilations in which the characters of our favourite video games are replaced by Shrek, the green ogre from the American studio DreamWorks. Behind this phenomenon lie a practice, modding, and a concept, the video game mod.

A mod, short for “modification”, refers to the alteration of an existing video game by a third party outside its authors, through the addition of one or more pieces of software. The elements modified can be as varied as they are numerous: a character’s appearance, new levels and missions, a change to a gameplay mechanic or improved graphics.

It is, in reality, the public’s appropriation of the video game work. Some mods have been so successful that they have become fully fledged video games in their own right: Counter-Strike, originally designed as a mod for Half-Life, DotA, born from a custom map for Warcraft III, or the battle royale PUBG, whose origins go back to a mod for ARMA 2.

Behind this abundant creativity, however, lies a complex legal tangle, at the crossroads of copyright and contract law. The practice is widespread, but is it legal?

I. The legal status of video games and its impact on the classification of mods

A. The video game, a complex work protected by copyright

To begin with, it is worth going back over the legal classification of video games.

Case law and legal scholarship abound with legal definitions of the video game. But if only one fairly comprehensive definition had to be kept, it would come from Article 220 terdecies of the French General Tax Code, which describes it as “any leisure software made available to the public on a physical medium or online, incorporating elements of artistic and technological creation, offering one or more users a series of interactions based on a scripted storyline or simulated situations and taking the form of animated images, with or without sound”.

The video game therefore contains a software dimension inseparable from other components, each protected by copyright as a work of the mind. A work of the mind is understood as a creation resulting from intellectual or artistic activity.

Under Article L. 112-1 of the French Intellectual Property Code, copyright protects all works of the mind, whatever their kind, form of expression, merit or purpose. However, a work of the mind is only protected if it meets two cumulative criteria developed by case law:

• a creation of form (a mere abstract idea is not enough);
• originality, understood as the imprint of the author’s personality.

Article L. 112-2 sets out, by way of illustration, a non-exhaustive list of protected works, in which the video game does not expressly appear. In the absence of a dedicated regime, its classification has been shaped by case law.

Since the Atari v. Valadon (1986) and Cryo (2009) rulings, the video game has therefore been regarded as a complex work of the mind, made up of a plurality of elements (software, database, multimedia content, script, music, gameplay, characters, scenery…), each subject to the legal regime specific to its nature.

B. The prerogatives conferred by copyright

On this basis, the authors of a video game enjoy two kinds of prerogatives.

Economic rights give their owner control over the economic exploitation of the work. Governed by Articles L. 122-1 et seq. of the French Intellectual Property Code, assignable and transferable, they take the form of three prerogatives: the right of reproduction, the right of performance, which covers any form of communication of the work to the public, and the right of adaptation and translation, which allows the author to control transformations of their work, notably the creation of derivative works.

Moral rights, for their part, protect the author’s non-economic interests, as they reflect the personal bond between the author and their creation. Enshrined in Article L. 121-1 of the French Intellectual Property Code, they are perpetual, inalienable and imprescriptible, and take the form of four prerogatives: the right of disclosure, the right to respect for the integrity of the work, which allows the author to object to any modification likely to distort it or harm their honour, the right of attribution, and the right of withdrawal or reconsideration, more rarely used in practice.

C. The mod, a composite work subject to conditions

From the legal classification of a video game as a work of the mind, we can deduce that of a mod. A mod is in fact a “composite” or “derivative” work within the meaning of Article L. 113-2, paragraph 2, of the French Intellectual Property Code, which defines it as “a new work into which a pre-existing work is incorporated without the collaboration of the latter’s author”. Article L. 113-4 further specifies that “the composite work is the property of the author who created it, subject to the rights of the author of the pre-existing work”.

Several lessons emerge from the combination of these two provisions.

First, the player-creator can only claim ownership and protection of their mod if it is original. It must also take sufficient distance from the pre-existing game to produce content that breaks free of the original model. Thus, a mere graphical overhaul will hardly be protectable, for lack of sufficient creative contribution. Conversely, a mod introducing a new plot, original game mechanics or a world of its own may claim protection. In that case, the player-creator will enjoy all the economic and moral rights mentioned above over their work.

However, the possibility of creating a mod and its protection remain precarious, since they are exercised subject to the rights of the owner of the pre-existing work.

The very existence of a mod can be prohibited by the authors of the original video game. Likewise, the commercial exploitation of a composite work is strictly subject to the prior authorisation of those same authors. Similarly, under the right to respect for the integrity of the work, developers and publishers can object to any alteration of their video game that would distort its spirit or harm their reputation, for example a mod inserting pornographic, racist or violent content into a family-friendly world.

Without such authorisation, the mod amounts to infringement, within the meaning of Articles L. 335-2 et seq. of the French Intellectual Property Code. The infringer is then liable to criminal penalties as well as to compensating the rights holder for the harm suffered, through a civil infringement action.

In practice, these authorisations are mainly managed contractually, through End User Licence Agreements (EULAs) and content creation licences.

II. The contractual framework: publishers authorising modifications

A. The use of EULAs

Publishers manage their relationships with players through End User Licence Agreements. These are contracts of adhesion containing a set of non-negotiable terms determined in advance and generally accepted with a simple click. Among them are the clauses governing permissions relating to modding.

Policies vary widely from one publisher to another. Mojang, publisher of Minecraft, explicitly allows modification of its game and recognises modders’ ownership of their original creations, requiring only a non-exclusive licence of use. Bethesda takes a similar approach with Skyrim, building in native mod support via its Creation Kit. Valve, owner of Steam, takes an intermediate position, encouraging modding through the Steam Workshop while strictly regulating monetisation. Activision-Blizzard includes a full assignment of ownership of any derivative work. Nintendo embodies the archetype of the most repressive doctrine: the Japanese publisher allows no mods and vigorously penalises any attempt to create them.

Rockstar Games, publisher notably of the GTA franchise and most recently GTA 5, takes a mixed approach: single-player mods are tolerated, but any modification affecting the online game is severely punished. The publisher did not hesitate to sue the creators of the re3 and reVC mods in 2021, before buying the modding platform FiveM for 20 million dollars in 2023, turning a community it had been chasing into a controlled source of revenue, with an official marketplace for paid mods planned for GTA 6.

The validity of these clauses is not, however, absolute under French law.

B. The incompatibility of general assignment clauses with French law

An analysis of French law reveals the legal fragility of these contractual provisions, which run up against several founding principles of copyright.

First, Article L. 131-1 of the French Intellectual Property Code provides that “the global assignment of future works is void”. The player-creator cannot, in principle, assign to a publisher in advance the rights in works that do not yet exist. Yet EULAs, by design, organise precisely an advance and undifferentiated assignment covering all the creations the player might make, in clear breach of this principle.

Second, Article L. 131-3 makes the transfer of copyright subject to each assigned right being mentioned separately, and to the scope of exploitation being precisely defined in terms of extent, purpose, place and duration. EULA clauses, which generally simply refer to “all rights” of the player without further detail, are in direct conflict with this specificity requirement. This is what led the Paris Court of First Instance, in UFC-Que Choisir v. Valve of 17 September 2019, to declare void an unfair clause by which Valve claimed rights over “any user-generated content”.

Finally, Article L. 121-1 makes moral rights perpetual, inalienable and imprescriptible. From this inalienability, case law has inferred not only that moral rights cannot be assigned, but also that they cannot be waived in advance and in general terms. It follows that developers cannot set aside the player-creator’s moral rights over their mod.

Publishers’ claims are thus confined to the economic sphere and, more precisely, to the strict limits set by legislation.

III. Statutory exceptions: narrow but real openings

The French Intellectual Property Code also provides for several exceptions to the author’s exclusive rights, some of which may, in theory, benefit modders.

The first is the private copying exception (Article L. 122-5, 2°), which allows reproductions strictly reserved for the copier’s private use. Its practical value in modding, however, remains slight: software is governed by a special regime, defined in Article L. 122-6-1, II, which only allows a single backup copy. Above all, as soon as the mod is shared online, the private use condition disappears.

The interoperability exception (Article L. 122-6-1, IV), on the other hand, proves more helpful. It allows software to be decompiled where this is indispensable to obtain the information needed for its interoperability with other programs. As a mandatory rule, this exception cannot be excluded by contract and may justify certain modding tools, provided they do not harm the normal exploitation of the game.

Finally, there is the parody, pastiche and caricature exception (Article L. 122-5, 4°), particularly suited to humorous mods, like the Shrek mods mentioned in the introduction. To rely on it, however, one must respect the “rules of the genre” developed by case law: a clear humorous intention, no risk of confusion with the original work and no intention to harm its author.

These exceptions are, however, narrowly interpreted and remain subject to many conditions. They cannot legitimise large-scale modding, particularly when it is accompanied by public distribution or commercial exploitation.

Conclusion

At the end of this analysis, the mod appears as a paradoxical legal figure: both a composite work that may be protected for the benefit of its creator, and a creation whose very existence depends on the tolerance of the original game’s publisher. While French copyright law can defeat the general assignment clauses in EULAs and guarantees the inalienability of the player-creator’s moral rights, it must be acknowledged that this framework remains ill-suited to the reality of an industry where millions of creations emerge simultaneously, behind pseudonyms and avatars.

In practice, though, some publishers willingly turn a blind eye to this legal grey area: tolerating modding keeps a fan community alive, extends the game’s life well beyond its usual commercial cycle, and generates free visibility that translates into advertising revenue, follow-on sales and greater fame. The perpetual clash of interests is thus gradually giving way to collaborative models: like Linden Lab with Second Life, some publishers now recognise players’ full ownership of their creations, including for commercial purposes, turning the modding community into a genuine engine of the game’s longevity. Rockstar Games’ purchase of FiveM is the most recent illustration: rather than prohibit, control and monetise.

Instead of confining players’ creativity within a contractual straitjacket, the future of modding no doubt lies in this path of mutually beneficial collaboration, where each side gains by recognising the other’s creative contribution.

Bibliography

Legislation

• French Intellectual Property Code, Art. L. 112-1, L. 112-2, L. 113-2, L. 113-4, L. 121-1, L. 122-1 et seq., L. 122-5, L. 122-6-1, L. 131-1, L. 131-3, L. 335-2 et seq.
• French General Tax Code, Art. 220 terdecies

Case law

• Paris Court of Appeal, Atari v. Valadon, 1986
• Cass. 1re civ., Cryo, 2009
• Paris Court of First Instance, UFC-Que Choisir v. Valve, 17 September 2019
• Cass. 1re civ., 23 October 2024, No. 23-13.738

Legal scholarship

Books

• G. Brunaux, Le jeu vidéo, un objet juridique identifié, Mare & Martin, 2019
• P. Mouron, G. Rabu, Droit du jeu vidéo, Larcier, 2025

Dissertations

• T. Espilondo, Le statut et les droits relatifs aux créations réalisées par les joueurs de jeux vidéo. Étude comparative franco-québécoise, master’s thesis in law, Université Laval / Université Paris-Saclay, 2022
• M. P. Rabiolo, Legal Dimensions of Video Game Modding. A Comparative Analysis of EU, US, and International Legal Frameworks, Master’s Thesis in European and International Trade Law, Department of Business Law, Lund University, 2024

Terms of use

• Mojang Studios, Minecraft End User License Agreement, available at minecraft.net
• Bethesda Softworks, Skyrim Creation Kit End User License Agreement, available at bethesda.net
• Valve Corporation, Steam Subscriber Agreement, available at store.steampowered.com
• Activision Blizzard, End User License Agreement, available at activision.com
• Nintendo, Nintendo Account Agreement, available at accounts.nintendo.com
• Take-Two Interactive, Rockstar Games Social Club Terms of Service, available at socialclub.rockstargames.com

Online sources

• « Take Two dépose finalement plainte contre les créateurs des modes re3 et reVC », Rockstar Mag’, 3 September 2021
• “Take-Two Just Explained Why It Bought FiveM for GTA 6”, GTA Boom, 7 May 2026

Moez RAISCo-founder, publication director and lawyer in intellectual property and digital law

https://lexludica.com/en/articles/the-mod-creation-under-constraints