Introduction
Intellectual property law grants exclusive rights over intangible creations, but the nature and purpose of these rights vary significantly across different regimes. This essay will critically discuss the differences between the infringement tests in UK copyright and trade mark law, focusing on their treatment of consumer perception, market impact, and the scope of the rights granted. It will be argued that while the infringement tests are indeed distinct, these differences are largely justified. They are a direct and logical consequence of the different normative goals that each area of law seeks to achieve. Copyright law is fundamentally author-centric, designed to incentivise creation by protecting original expression. In contrast, trade mark law is market-centric, designed to protect the source-identifying function of a mark, thereby preventing consumer confusion and safeguarding commercial goodwill. The tailored nature of each infringement test is therefore not an inconsistency, but a necessary feature for each right to function effectively in line with its underlying purpose.
The Normative Justifications of Copyright and Trade Mark Law
To understand why the infringement tests differ, it is essential first to establish the foundational justifications for copyright and trade mark protection. Although both are forms of intellectual property, their aims are quite different.
Copyright law in the UK is primarily underpinned by a utilitarian or incentive-based justification. As articulated by scholars like Bently et al. (2022), the law provides authors and creators with a limited-term monopoly over their work. This is codified in the Copyright, Designs and Patents Act 1988 (CDPA 1988), which grants the owner a set of exclusive rights, such as the right to copy the work (s.16). The purpose of this monopoly is to allow creators to control the exploitation of their work and thereby receive remuneration for their 'skill, labour and judgment' (Ladbroke (Football) Ltd v William Hill (Football) Ltd [1964] 1 WLR 273). This financial reward is intended to act as an incentive for the creation and dissemination of new literary, dramatic, musical, and artistic works, which ultimately benefits society as a whole by enriching the public domain. The focus is therefore on protecting the integrity of the creative expression itself and rewarding the author.
Trade mark law, governed by the Trade Marks Act 1994 (TMA 1994), has a different set of justifications rooted in market economics and consumer protection. The primary function of a trade mark is to act as a 'badge of origin', indicating the commercial source of goods or services. This serves two key purposes. Firstly, it protects consumers by enabling them to make informed purchasing decisions and avoid being deceived as to the origin and, by extension, the quality of products (Wadlow, 2017). Secondly, it protects the investment and 'goodwill' that a trader has built up in their brand. By preventing competitors from using confusingly similar signs, the law ensures that the trade mark owner reaps the benefits of their reputation. The core justification, therefore, is not about incentivising creativity but about ensuring market transparency and fair competition.
Differences in Consumer Perception
The contrasting justifications of the two rights are clearly reflected in the role that consumer perception plays in their respective infringement tests. In trade mark law, it is central; in copyright law, it is largely irrelevant.
For trade mark infringement under section 10(2) of the TMA 1994, the key question is whether a defendant’s use of a sign creates a 'likelihood of confusion on the part of the public'. This test places the 'average consumer' at the heart of the inquiry. As established by the Court of Justice of the European Union in foundational cases like Sabel v Puma AG [1998] ETMR 1, the court must assess the issue through the eyes of a consumer who is reasonably observant but who relies on an 'imperfect picture' of the mark they hold in their memory. The global assessment involves comparing the visual, aural, and conceptual similarities of the marks and the similarity of the goods or services in question. This direct focus on the consumer’s mental state is a logical extension of the trade mark’s origin-guaranteeing function. If the consumer is not confused, the mark's function as a badge of origin is not undermined, and in many cases, no infringement occurs.
By contrast, the test for primary copyright infringement has no such requirement. Under section 16 of the CDPA 1988, infringement occurs when a person, without permission, does any of the acts restricted by the copyright, the most common of which is copying. The test for copying is whether the defendant has reproduced a 'substantial part' of the claimant's work. In Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000] 1 WLR 2416, the House of Lords confirmed that 'substantial part' is a qualitative, not a quantitative, measure, focusing on the originality of the part that has been taken. The court undertakes an objective comparison of the two works to see if the core of the author’s original expression has been appropriated. The perception of a consumer or member of the public is not part of this test. This is justified because the harm copyright seeks to prevent is the misappropriation of the author’s creative labour, not the deception of the public. The right is infringed the moment a substantial part is copied, regardless of whether anyone is confused by it.
Differences in Market Impact
The role of market impact also differs significantly between the two regimes, again highlighting their distinct normative foundations.
In copyright law, direct financial harm or a negative market impact is not a prerequisite for proving primary infringement. The act of copying a substantial part is, in itself, the infringing act. An amateur who copies a poem for a personal blog with no commercial intent infringes just as much as a major publisher who sells thousands of copies. While the extent of market harm is a crucial factor in determining the quantum of damages or an account of profits at the remedies stage, it does not form part of the initial liability test. The wrong is the unauthorised use of the author’s protected expression.
In trade mark law, however, market impact is a direct and essential component of certain infringement tests. This is most evident in the protection afforded to marks with a reputation under section 10(3) of the TMA 1994. This provision prevents the use of a similar sign which, without due cause, takes 'unfair advantage' of, or is 'detrimental' to, the distinctive character or repute of the famous mark. This type of infringement, often known as dilution, can occur even where there is no likelihood of confusion. The harm here is purely economic and reputational. In L'Oréal SA v Bellure NV [2010] RPC 1, the court identified harms such as 'blurring' (weakening the mark's distinctiveness), 'tarnishment' (damaging its reputation), and 'free-riding' (taking unfair advantage of the mark's marketing effort). These are all forms of market-based harm that damage the economic value and 'advertising function' of the trade mark. This protection is justified because trade marks are commercial assets whose value and power of attraction are worthy of protection in their own right, separate from the prevention of simple consumer confusion.
Differences in the Scope of Exclusive Rights
Finally, the scope of the exclusive rights granted by copyright and trade mark law is fundamentally different, particularly concerning the concept of independent creation.
Copyright protects the expression of an idea, not the idea itself. A crucial consequence of this is that independent creation is a complete defence to an allegation of copyright infringement. If two authors, working independently, happen to create identical or very similar novels, neither infringes the other's copyright. This is because copyright law’s purpose is to incentivise new creative acts. So long as a work is original (i.e., it originates from the author), it is protected, and it does not infringe an earlier work unless it was actually copied from it. The right is a right to prevent copying, not a true monopoly over the form of expression.
Trade mark law operates differently. The owner of a registered trade mark has an exclusive right that is effective against any other party using an identical or confusingly similar mark in the course of trade for relevant goods or services. Independent creation is not a defence. If a business innocently and independently devises a brand name that is confusingly similar to a pre-existing registered trade mark, its use will still constitute infringement. This absolute nature is justified by the trade mark’s function. The goal is to create a clear and unambiguous system of source-identifiers in the marketplace. Allowing two confusingly similar marks to co-exist, regardless of how they were created, would lead to the very consumer confusion and market disruption that the law is designed to prevent. Therefore, the right must be exclusive in the market to be effective.
Conclusion
In conclusion, the infringement tests in copyright and trade mark law show marked differences in their approach to consumer perception, market impact, and the scope of their exclusive rights. Consumer perception is central to trade mark infringement but irrelevant to copyright infringement. Market impact is a direct element of liability for some forms of trade mark infringement but not for primary copyright infringement. Finally, copyright permits independent creation, whereas trade mark law grants a more absolute right against confusingly similar signs in the market.
This essay has argued that these differences are not only present but are entirely justified by the distinct normative foundations of each right. The author-centric, incentive-based model of copyright logically leads to an infringement test focused on protecting the author's original expression from being copied. The market-centric, consumer-focused model of trade mark law necessarily results in tests that police consumer confusion and protect the commercial value of a brand in the marketplace. The legal frameworks are therefore appropriately tailored to their specific objectives, ensuring that both creative expression and fair market competition are effectively protected.
References
Bently, L., Sherman, B., Gangjee, D. and Johnson, P. (2022) Intellectual Property Law. 6th edn. Oxford: Oxford University Press.
Copyright, Designs and Patents Act 1988.
Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000] 1 WLR 2416.
Ladbroke (Football) Ltd v William Hill (Football) Ltd [1964] 1 WLR 273.
L'Oréal SA v Bellure NV [2010] RPC 1.
Sabel v Puma AG [1998] ETMR 1.
Trade Marks Act 1994.
Wadlow, C. (2017) The Law of Passing-Off: Unfair Competition by Misrepresentation. 5th edn. London: Sweet & Maxwell.

