In the business world, where the signed document often seems to govern all relationships, the contract does not say everything. In addition to negotiated clauses, unwritten rules have a profound influence on day-to-day professional activity: these are commercial practices. Often overlooked, they are a source of law in their own right, capable of supplementing, interpreting or even contradicting the law or the contract itself. For any company, understanding their nature and scope is essential in order to secure its operations and avoid costly disputes. This study aims to give a precise definition and explore their future.
What is commercial use?
A trade usage arises from a professional habit which, through repeated practice and recognition within a given environment, acquires normative force. For a simple habit to become a legally recognised usage, legal doctrine and case law require a number of objective criteria to be met in order for it to be valid.
A general, constant and well-known practice
Three elements are traditionally required to characterise a usage. Firstly, there must be a general practice, i.e. one followed by the majority of players in a sector or market place. It is not a question of isolated behaviour. The practice must be repeated on a regular basis, although the speed of modern trade, particularly in e-commerce, can accelerate the creation of new practices. Finally, the practice must be sufficiently well known: it must be known to the players in the sector concerned, who are then presumed to refer to it in their transactions.
Doctrinal distinction: de facto use vs. de jure use (custom)
Legal doctrine defines a classic distinction, although its boundaries are porous. On the one handde facto usealso known as usage conventionalis seen as a practice used to interpret the will of the parties in the event of silence or ambiguity in a contract or offer. It applies because it is presumed that the contracting parties tacitly intended to abide by it, as suggested by articles 1194 and 1160 of the Civil Code. On the other handuse of rightCommercial custom is considered to be a genuine objective rule of law. It is self-imposed, independently of the will of the parties, because the professional world recognises it as binding. The best-known example is the presumption of passive solidarity between commercial co-debtors, which derogates from the principle of private law (ordinary law).
What are the different types of commercial use?
The scope of application of usages varies according to their geographical or sectoral scope, ranging from very local practices to standards governing world trade. This is a key point for contract management.
The local customs are confined to a specific geographical area: a city, a port or a commercial centre. They may govern, for example, delivery terms in the port of Marseille (sometimes governed by maritime law) or payment terms specific to the Bordeaux wine market or the Paris marketplace for certain sectors. The law itself sometimes refers to them, as in the case of commercial leases for the duration of the notice period (article L. 145-9 of the French Commercial Code), where these local customs are well established.
The national customs apply throughout France. Some are general, such as the presumption of commercial solidarity or the practice of price reduction in the event of minor lack of conformity. Others are specific to a sector, such as the anatocism (capitalisation of interest) in bank current accounts, which derogates from the rule in article 1343-2 of the Civil Code, or the conditions of sale in agricultural sectors at national level.
Finally, the international trade practices have acquired crucial importance with globalisation. They make it possible to overcome the diversity of national legislation. Organisations such as the International Chamber of Commerce (ICC) have helped to formalise them, notably through the Incotermss, which standardise the obligations of sellers and buyers with regard to supply and delivery, or the Uniform Customs and Practice (UCP) for documentary credits. These uses form the core of the lex mercatoria and the specificities of international tradeA body of rules specific to the global business community, sometimes referred to as international trade law.
What is the legal force of usages and their enforceability?
The normative value of a usage is measured by its ability to prevail over the law, the contract and the various parties. For a more in-depth understanding of the interactions between the various sources and their hierarchy, consult our Frequently asked questions about the sources of commercial law.
The hierarchy of norms: usage versus law and contract
The relationship between use and the law is nuanced. Faced with a suppletive law (which applies only in the absence of a contrary intention), usage generally prevails, as it is considered to be better suited to business practice. On the other hand, the principle is that usage cannot derogate from a rule of law. mandatory lawIn other words, public policy. However, case law has established practices contra legem (contrary to the law), such as commercial solidarity or anatocism, justified by the needs of credit and the specific nature of commercial law. However, the primacy of the will of the parties remains: they can always set aside a suppletive usage by an express clause in their contract.
Enforceability of use: a variable-geometry application
A usage does not automatically apply to everyone. Case law makes a clear distinction depending on the status of the parties:
- Between professionals in the same sector or in the same placeIn this case, the use is presumed to be known and therefore enforceable. Silence on the part of a tradesperson implies acceptance of the practice in his or her environment.
- With regard to a non-professional or a third party outside the sectorUsage is not enforceable ipso jure. It must be proved that the party was aware of it and consented to its application, even tacitly.
Review by the Cour de cassation: between qualification and censure
The Court of Cassation plays an essential role in recognising and delimiting the force of custom. Its review is twofold. On the one hand, it qualifies the nature of the usage: is it a simple practice (de facto usage) subject to the sovereign assessment of the trial judges, or is it a genuine rule of law (de jure usage), the breach of which may give rise to a right of cassation? The distinction is subtle. For example, commercial solidarity is treated as a rule of law. On the other hand, the Court censures usages that run counter to public policy or fundamental mandatory laws, thus marking the limits of the normativity of professional practices.
How do you prove commercial use in court?
In commercial matters, proof is free (article L. 110-3 of the French Commercial Code). The existence of a usage may therefore be established by any means. For an exhaustive understanding of methods of proof in commercial lawTo find out more, including the challenges of digital technology, read our dedicated article.
The burden of proof and the role of the judge
It is up to the person claiming a usage to prove it. However, if the usage is well known and established by case law (as a usage de droit), the judge is deemed to be familiar with it and may apply it ex officio, given his or her position. Consular judges, who often come from the business world, may also use their personal knowledge to assess the existence of a usage.
Traditional methods of proof: the parer in the lead
As Professor Mousseron points out in his famous book treatise on commercial lawthe preferred and most formal method of proof is the motherland. This is a written attestation issued by a competent professional organisation (Chamber of Commerce and Industry, trade association), certifying the existence, content and scope of a practice in a given environment. Although it is not binding on the judge, it has strong moral authority. Other means are also accepted: standard contracts, offer confirmations, testimonials, expert reports or previous court rulings recognising usage.
Modern challenges: from evidential freedom to digital formalism
The principle of freedom of evidence is now faced with the realities of digital commerce. The increasing dematerialisation of exchanges imposes a certain evidentiary formalism, in particular via electronic writing and the electronic signature, which provides a framework for this freedom. This raises the problem of proving the uses made of online platforms, where an offer may be accepted by thousands of users. Similarly, "agreements on evidence", whereby the parties themselves lay down the rules of evidence applicable to their relationship, may limit or organise the way in which a usage can be demonstrated in the event of a dispute.
The future of commercial use: between relative decline and new forms of expression
Analysing commercial usages today requires us to go beyond a simple description of their regime to consider their place in a rapidly changing legal landscape. For this reason, prospective research is necessary.
The apparent decline of traditional customary sources
Several factors explain why customary usage, in its most traditional and spontaneous form, seems to be losing ground. Legislative and regulatory inflation is tending to regulate more and more sectors, leaving less room for unwritten rules. The standardisation of contracts and the predominance of the signed written document, particularly in international relations, are pushing companies to provide for everything in explicit clauses, thereby reducing the complementary role of custom.
The rise of soft law: the revival of custom through neo-corporatism
Yet this decline is only relative. Practices are re-emerging in more structured forms, as a new expression of normativity. This phenomenon, sometimes referred to as neo-corporatism, sees professional organisations play a quasi-legislative role. They draw up codes of conductethical charters or standard contracts which, although not emanating from the State, acquire considerable normative force. This is the case when a distributors' union establishes standards for the profession. Jurisprudence increasingly recognises these documents as benchmarks for assessing the behaviour of players, going so far as to consider them as genuine binding legal practices.
Uses in the digital age: instant training and new challenges
E-commerce and online platforms are creating fertile ground for a new kind of usage. Unlike traditional practices that took time to establish, digital practices can be formed almost instantaneously on an online site or platform. This speed overturns the traditional criteria of consistency and duration. The difficulty for a judge is to establish and prove a use that evolves so quickly. This issue represents a major challenge for commercial law and illustrates the tremendous adaptability of business practices.
The importance of legal advice in mastering commercial practices
Navigating the world of commercial usages can be complex. Their unwritten nature, the subtle distinctions between their categories, the uncertainty as to their enforceability or their relationship with the law make a detailed legal analysis essential. A lawyer with expertise in commercial law can identify the relevant usages, secure your contractual relations integrating or excluding certain practices, and managing disputes arising from their application. For this reason, the basis for any action is appropriate legal advice. To analyse the impact of practices on your business and secure your contractual relations, our firm is at your disposal.
Sources and further reading
In addition to the Commercial Code (in particular L. 110-3 and L. 145-9) and the Civil Code (1194, 1160, 1343-2), in-depth legal research could be based on the following bibliography:
- Mousseron, Jean-Marc. Business law. LGDJ, 11th edition.
- Terré, François. General introduction to law. Dalloz.
- Ripert, Georges & Roblot, René, by Delebecque, Philippe & Germain, Michel. A treatise on commercial law. LGDJ.
- Fouchard, Philippe, Gaillard, Emmanuel & Goldman, Berthold. Treaty on International Commercial Arbitration. Litec.
- "Custom in commercial law", Quarterly review of commercial and economic law (RTD Com).
- Comment under Cass. com. 15 November 2011, on proof of use.
- Cass. civ. 1re, 12 July 2005; Cass. com. 24 January 2018.
- African uniform business law under OHADAfor a study on the Uniform Act.
- An old reference book on the subject remains a starting point for a historical study.
- All legal research journals offer relevant content on this constantly evolving topic.
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