Introduction
The doctrine of restraint of trade concerns the enforceability of contractual clauses that seek to limit a person's freedom to carry on their trade, business, or profession. At its core, the doctrine represents a fundamental tension between two competing public policy objectives: the freedom of individuals to enter into contracts as they see fit, and the public interest in promoting free competition and ensuring individuals are not prevented from using their skills to earn a living. The law in this area has undergone a significant evolution. Initially, the common law adopted a position of outright hostility towards such clauses, viewing them as void. However, this rigid stance has given way to a more flexible and pragmatic approach centred on the test of reasonableness. This essay will critically analyse this development, arguing that while the modern reasonableness test is more attuned to commercial realities, its application has introduced its own set of uncertainties, particularly in balancing the interests of the parties and the public.
The Early Hostility Towards Restraints
The historical starting point for the doctrine of restraint of trade was a general prohibition. The courts viewed any agreement that restricted a person’s ability to trade as being contrary to the public interest and therefore void. The classic early authority is Dyer's Case (1414), where a dyer had given a bond not to practice his trade in the same town as the plaintiff for six months. The court reacted with anger, reportedly threatening to imprison the plaintiff for procuring such a bond, and held the restriction to be void. This early and uncompromising position was based on the public policy concern that such restraints deprived both the individual of their livelihood and the public of a useful service (McKendrick, 2022).
This strict rule was gradually relaxed. In the seminal case of Mitchel v Reynolds (1711), the court distinguished between 'general' restraints, which were void, and 'particular' restraints, which could be valid if supported by good consideration and if the restraint was reasonable. A general restraint was one that applied throughout the entire kingdom, whereas a particular restraint was limited in its geographical scope. Lord Macclesfield reasoned that a limited restraint could be justified if it was necessary to protect a legitimate interest, such as the goodwill of a business that had been sold. This case marked an important first step away from total prohibition, introducing the idea that not all restraints were automatically against the public interest. However, the law still maintained a strong presumption against their validity.
The Modern Test of Reasonableness: The Nordenfelt Shift
The definitive shift towards the modern approach occurred in the House of Lords decision of Nordenfelt v Maxim Nordenfelt Guns and Ammunition Co Ltd (1894). Mr Nordenfelt, an armaments manufacturer, sold his business and agreed not to manufacture guns or ammunition anywhere in the world for 25 years. He also agreed not to compete in any way with the company for the same period. The House of Lords held that the old distinction between 'general' and 'particular' restraints was no longer relevant in an age of global commerce. Instead, the central question was whether the restraint was reasonable.
Lord Macnaghten established the modern two-stage test. First, the clause must be reasonable as between the parties, meaning it must protect a legitimate proprietary interest of the covenantee and be no wider than is reasonably necessary to protect that interest in terms of its duration, geographical scope, and the activities it restricts. Second, the clause must be reasonable in the public interest. On the facts, the worldwide restraint on manufacturing guns was upheld because the company's business was global and the restriction was necessary to protect the very valuable goodwill that Nordenfelt had sold. However, the wider clause preventing any form of competition was deemed unreasonable and was severed from the contract. The Nordenfelt decision established that all restraints of trade are prima facie void, but they can be enforced if the party seeking to rely on the clause can prove that it is reasonable. This remains the foundational principle of the modern law.
Application of the Reasonableness Test in Context
The application of the reasonableness test is highly fact-sensitive and varies depending on the context in which the restraint arises. The courts are generally more willing to uphold restraints in some situations than in others, reflecting differences in bargaining power and the nature of the interest being protected.
Employment Contracts
In the context of employment contracts, the courts apply the reasonableness test with particular scrutiny. This is due to the inherent inequality of bargaining power between an employer and an individual employee. The law recognises that an employer has a legitimate interest in protecting its business, but this does not extend to merely protecting itself from competition from a former employee. As established in Herbert Morris Ltd v Saxelby (1916), the only interests that an employer can legitimately protect are its trade secrets and its trade connections (i.e., its customer base). A clause that simply prevents an employee from using their own skill and knowledge, even if acquired during their employment, will be held to be an unreasonable restraint on trade. For example, in Fitch v Dewes (1921), a lifelong restraint on a solicitor's clerk from working within a seven-mile radius of the town was upheld because it was necessary to protect the firm's client connections. In contrast, a wider clause preventing an employee from working for any rival business may be struck down as being too broad.
Sale of a Business
By contrast, the courts are generally more willing to enforce restraint of trade clauses in contracts for the sale of a business. The rationale is that the parties are usually in a more equal bargaining position, and the purchaser of the business has paid a price that includes the business's goodwill. It is therefore seen as legitimate for the purchaser to protect this investment by preventing the seller from setting up a competing business in the immediate vicinity. The facts of Nordenfelt itself illustrate this principle. The global scope of the restraint was considered reasonable because the business being sold operated on a global scale. This approach recognises that without an enforceable restraint, the goodwill for which the purchaser has paid would be significantly diminished or even worthless (Peel, 2021).
The Challenge of Uncertainty and the Role of Severance
While the shift to a reasonableness test has made the law more flexible, it has also created a degree of uncertainty. What is considered 'reasonable' depends heavily on the specific facts of each case, making it difficult to predict with certainty whether a particular clause will be upheld. This can lead to costly litigation.
To mitigate the harshness of a clause being declared entirely void, the courts developed the doctrine of severance, often known as the 'blue pencil test'. This allows a court to strike out the unreasonable parts of a clause, leaving the reasonable parts intact and enforceable, provided that doing so does not alter the fundamental character of the contract and the remaining part makes grammatical sense. For a long time, the test was applied restrictively, meaning courts could only cross out words, not add them or rewrite the clause.
However, the Supreme Court's decision in Tillman v Egon Zehnder Ltd (2019) has significantly developed this area. The case concerned a clause preventing a former employee from being "concerned or interested in" any competing business. The term "interested in" was potentially too wide as it could prevent even a minor shareholding in a public company. The Supreme Court confirmed that words could be severed from a clause if two conditions were met: first, the unenforceable provision could be removed without needing to add to or modify the remaining words (the traditional blue pencil test), and second, the removal of the words would not generate any major change in the overall effect of all the post-employment restraints in the contract. By applying this approach, the court was able to sever the words "or interested in", rendering the remainder of the clause enforceable. This decision arguably makes it easier for employers to enforce poorly drafted restrictive covenants, potentially shifting the balance of power back towards them, though it also provides clarity on the courts' powers of severance.
Conclusion
In conclusion, the legal principles governing restraint of trade have developed significantly from a rigid rule of invalidity to a flexible, context-dependent test of reasonableness. This evolution, driven by landmark cases like Mitchel v Reynolds and Nordenfelt, reflects the law's attempt to adapt to changing commercial practices while balancing the competing interests of freedom of contract, protection of legitimate business interests, and the public policy of promoting competition. The modern approach, which scrutinises clauses in employment contracts more strictly than those in business sales, demonstrates a pragmatic understanding of commercial realities. However, the flexibility of the 'reasonableness' standard inevitably leads to a degree of legal uncertainty. The recent development in the law of severance, as seen in Tillman v Egon Zehnder, shows the courts continuing to refine the doctrine, in this case providing a clearer path to saving an otherwise over-broad clause. The law has therefore moved from a blunt instrument to a more nuanced tool, but one which still requires careful judicial application to ensure a fair balance is struck in each individual case.
References
Dyer's Case (1414) YB 2 Hen V, vol 5, pl 26.
Esso Petroleum Co Ltd v Harper’s Garage (Stourport) Ltd [1968] AC 269.
Fitch v Dewes [1921] 2 AC 158.
Herbert Morris Ltd v Saxelby [1916] 1 AC 688.
McKendrick, E. (2022) Contract Law. 15th edn. Palgrave Macmillan.
Mitchel v Reynolds (1711) 1 P Wms 181.
Nordenfelt v Maxim Nordenfelt Guns and Ammunition Co Ltd [1894] AC 535.
Peel, E. (2021) Treitel on The Law of Contract. 15th edn. Sweet & Maxwell.
Tillman v Egon Zehnder Ltd [2019] UKSC 32.
