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The Death of Copyright Law's Idea/Expression Dichotomy

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About The Author

Ted Cook (Guest Contributor)

Ted is a history and politics graduate from the University of Sheffield and a Future Trainee Solicitor at Morgan Lewis and Bockius LLP. He is currently undertaking the LPC at BPP Holborn. Outside the law, Ted is an accomplished skier.

Ideas are cheap. Ideas are easy. Ideas are common. Execution is all that matters.

Casey Neistat

Many commentators and judges agree that it is trite law that copyright protection can subsist only in the expression of an idea and not the idea itself. This principle – known as the ‘idea/expression dichotomy’ (the Dichotomy) – has been outlined in the Guidance Notes to the Berne Convention for the Protection of Artistic and Literary Works 1978 (the Berne Convention):

A fundamental point is that ideas, as such, are not protected by copyright… But once that idea has been elaborated and expressed, copyright protection exists for the words, notes, drawings… in which it is clothed. In other words, it is the form of expression which is capable of protection and not the idea itself.

However, despite the fundamental status of the Dichotomy to intellectual property law, legislation has yet to provide the courts with any particular guide as to its operation. As a result, courts have had to establish their own framework in common law for distinguishing between, on the one hand, mere ideas and, on the other, sufficient expressions.

Yet the inflexibility of the Dichotomy has caused disagreement in the courts in a multitude of ways: several problems  have emerged following its application to real-life scenarios. Indeed, this article will demonstrate how, in acknowledgement of these issues, the courts have gradually moved away from the Dichotomy and have reached a point where its role in the law has been all but removed.

The Definition of Copyright

The Copyright, Designs and Patents Act 1988 (CDPA 1988) outlines the categories a work must fall into to be protected. Taken together, Section 1(1)(a) and Section 3(1) of the CDPA 1988 hold that these categories include ‘traditional’ areas of literary, dramatic, musical or artistic works to ‘non-traditional’ areas such as computer programs. In addition, Section 3(2) of the CDPA 1988 alludes to the Dichotomy by providing – in what is considered as a requirement for the ‘fixation’ of the work – that:

[C]opyright does not subsist in a literary, dramatic or musical work unless and until it is recorded, in writing or otherwise.

Beyond these sections of the CDPA 1988, however, no reference is made in English legislation to the operation of the Dichotomy. Therefore, to find confirmation of its need to be applied, regard must be had to a variety of international treaties. For example, Article 9(2) of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) expressly requires compliance with the Dichotomy, and Article 9(1) of TRIPS also demands signatories comply with Articles 1-21 of the Berne Convention, which includes the definition of the Dichotomy given above.

Furthermore, the Dichotomy is also outlined in Article 2 of the World Intellectual Property Organisation Copyright Treaty which provides that copyright protection extends to expressions but not ‘ideas, procedures, methods of operation or mathematical concepts.’  However, none of these treaties provide insight into how to differentiate between an idea and an expression. This role has therefore been delegated to the judiciary.

Difficulty in Defining the Dichotomy

Judicial opinions towards the Dichotomy have varied throughout the years. Early views were mostly positive: Yates J’s dissent in Millar v Taylor [1769], for example, made it clear that, once the originator of an idea communicates an idea into the public domain, it becomes common and the originator will retain no property rights over it. This approach also found support in the House of Lords in Hollinrake v Truswell [1894] 3 Ch D 420, where Davey LJ opined that:

Copyright… does not extend to ideas, or schemes, or systems, or methods; it is confined to their expression and if their expression is not copied the copyright is not infringed. 

The modern judiciary have been prepared to articulate a similar principle. Lloyd LJ, for example, made it clear in Baigent v The Random House Group Ltd [2007] that ‘copyright does not subsist in ideas; it protects the expression of ideas, not the ideas themselves’.

However, despite sustained affirmation of the Dichotomy over the years, concerns were also being raised that ideas and expressions had converged to the point that they had become inseparable. Awareness of this problem had grown partly due to the emergence of programming and software, though was also referred to by judges deciding on cases even in traditional areas of literary, dramatic and music works. This has led to judicial criticism of the Dichotomy’s inflexibility: for example, Lloyd LJ in Baigent v The Random House Group Ltd [2007] complained that:

[N]o clear principle is or could be laid down in cases in order to tell whether what is sought to be protected is on the ideas side of the dividing line, or on the expression side.

This lack of a clear explanation of the Dichotomy left the judiciary with the task of trying to rectify the problem. In doing so, however, there was much disagreement and confusion between the courts. For example, Lord Denning MR in Ladbroke (Football) Ltd v William Hill (Football) Ltd [1964] 1 All ER 465 placed particular emphasis on ideas in the mind and the consequences of their disclosure:

[O]nce [the idea] is written down, the writing is the subject of copyright. No one is entitled to copy it on the plea that it was only an idea.

However, this approach was rejected by Lord Hoffman in Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000]. In his view, the Dichotomy could not 'mean anything so trivial as' what Lord Denning MR had proposed. All this pointed towards the clear difficulty in defining exactly what the Dichotomy was intended to mean. 

Replacing the Dichotomy with a Test of Originality

The Position in English Law

Section 1(1)(a) of the CDPA 1988 sets down an additional requirement for copyright protection: that the work must be ‘original’. In University of London Press Ltd v University Tutorial Press Ltd [1916] 2 Ch 601, Peterson J made it clear that 'original' does not ‘mean that the work must be the expression of original or inventive thought'; instead, the expression of the idea must simply ‘not be copied from another work’. To achieve this, the author of the work must have applied ‘more than trivial labour, skill and judgement’ in expressing the idea in a tangible format, such as – on the facts of University of London Press Ltd v University Tutorial Press Ltd [1916] 2 Ch 601 – selecting which works went into a compilation and how they were organised.

This concept of originality was to form the basis of a change of pace regarding via the House of Lords' judgment in Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000]. This landmark case saw the Law Lords consider ‘non-literal’ copying, and examine the extent to which a qualitatively ‘substantial part’ of the work had been copied. In doing so, Lord Hoffmann opined that:

[C]ertain ideas expressed by a copyright work may not be protected because, although they are ideas of a literary, dramatic or artistic nature, they are not original, or so commonplace as not to form a substantial part.

This appeared to cast some doubt on the usefulness of the Dichotomy in copyright law in favour of a test for originality. Throughout the judgment, Lord Hoffmann appeared to collapse the Dichotomy into a test of originality based on whether a substantial part has been copied. The example of artistic copyright was used to provide that ‘the more abstract and simple the copied idea, the less likely it is to constitute a substantial part’.

Crucially, Lord Scott also advocated an approach of a similar nature. To determine whether infringement had occurred, he held it was necessary to look at the similarities between the works rather than their differences, considering them holistically.

This appears to be an express contradiction to the Dichotomy. In essence, the House of Lords in Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000] appeared to be suggesting that, where an idea has been expressed in enough detail, an alternate expression of the same idea will be held to have infringed upon the copyright on the initial idea. This ultimately suggests that the underlying idea is in fact protected by copyright.

This qualitative approach taken in Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000] was subsequently adopted by the courts in several cases. Of most interest is the case of Allen v Bloomsbury Publishing [2010], which concerned allegations that J.K. Rowling had used large parts of the claimant’s book when writing Harry Potter and the Goblet of Fire. In his judgment, Kitchin J held that the similarities between the initial book and J.K. Rowling's book upon which the claimant sought to rely on consisted of abstract ideas with a high level of generality and therefore did not form the expression of the ideas themselves. This demonstrates that the courts, instead of disregarding these claims outright as the Dichotomy would suggest, did undertake some consideration as to whether an idea is sufficiently detailed to warrant protection.

The Position in EU Law

Development in EU law - including the provisions of recent Directives and judgments from the European Court of Justice (ECJ) - have followed and adapted the approach articulated in taken in Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000]. For example, in Infopaq International v Dankse Dagblades Forening [2009] the ECJ concluded that copyright only subsists in work that is original in the sense that it is the author’s own ‘intellectual creation’.

That case concerned a computer program that reproduced excerpts from newspaper articles that, on some occasions, ranged in length, with some amounting to 11 words. The question before the ECJ was whether, via these short excerpts, the newspaper articles had been ‘reproduced in part’ under Article 2 of the Information Software Directive. In its decision the ECJ held that:

[I]t is only through the choice, sequence, and combination of those words that the author may express his creativity in an original manner and achieve a result which is an intellectual creation.

The ECJ therefore concluded that, based on this criteria, even a short extract from an article might reflect the author’s own intellectual creation and therefore be deemed ‘original’. There must thus be an element of novelty or merit in an author’s creation: in doing so, it could be argued that the wording suggests that for an expression to be protected it must stem from an original idea. If so, this provides the implication that the original idea warrants protection in itself.

The Court of Appeal considered this approach in Newspaper Licensing Agency v Meltwater Holdings BV [2011]. This case concerned the defendant’s subsidiary company searching media websites for key words of interest to its clients and then alerting its clients of these headlines. The answer to whether a licence was needed by the defendant depended on whether copyright subsisted in the ‘literary work’ of newspaper headlines and whether the extracts, some as short as 11 words, constituted a ‘substantial part’ of the article from which they were taken. The Court of Appeal held that the Infopaq International A/S V Dankse Dagblades Forening [2009] test did not relate to novelty or merit, but rather to origin and so did not exclude the traditional ‘skill, judgment and labour test’.

Importantly, neither the ECJ in Infopaq International A/S V Dankse Dagblades Forening [2009] nor the Court of Appeal in Newspaper Licensing Agency v Meltwater Holdings BV [2011] mentioned the Dichotomy once. Instead, both opted to consider the originality test, in what is a clear demonstration of the extent to which use of the Dichotomy has declined.

Application to Computer Software

In Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000], Lord Hoffman made a second proposition concerning the Dichotomy, suggesting that:

[A] copyright work may express certain ideas which are not protected because they have no connection with the literary, dramatic, musical or artistic nature of the work.

This view appears to offer clear criteria as to when the Dichotomy can be applied. However, problems remain: for example, if taken literally, it would suggest that software and computer programs are incapable of copyright protection. In many cases, judges have recognised that the Dichotomy is too inflexible to work for computer programs, as well as the fact that separating ideas from expressions of ideas is nearly impossible in sui generis databases because they are often entirely composed of factual information.

However, computer programs must be capable of copyright protection: they are explicitly referred to in the CDPA 1988, by virtue of The Copyright and Rights in Databases Regulations 1997.  Furthermore, Article 4 of the WIPO Copyright Treaty holds that:

[C]omputer programs are protected as literary works within the meaning of Article 2 of the Berne Convention.

The issue first arose in IBCOS Computers v Barclays Mercantile Highland Finance Ltd  [1994] FSR 275. Here, Jacob J avoided direct reference to the Dichotomy as a decisive test by referring to it as a ‘guide’. Instead, he adopted a holistic approach and examined the structure of the computer program as a whole in assessing infringement. It was held that infringement had occurred through ‘over-borrowing’, demonstrating that an assessment to see if a ‘substantial part’ of the idea had been copied works better in the context of computer programs.

In further cases involving software, the courts have shied away from adopting the Dichotomy, opting instead to assess if a substantial part had been copied. For example, in Navitaire v Easyjet Airlines [2004], Pumfrey J eroded the utility of the Dichotomy in two ways. Firstly, he reaffirmed the general applicability of Lord Hoffman’s pronouncement in Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000] that infringement would occur if a ‘sufficiently detailed’ idea had been taken. In this respect, Pumfrey J applied this to the ‘business logic’ of the program that was adopted, suggesting that there is a certain level of complexity inherent in an idea which, if copied, will constitute infringement. This is in direct contradiction of the Dichotomy’s exclusion of ideas from copyright.

Secondly, Pumfrey J had the opportunity to use the Dichotomy to decide the case, but instead argued that ‘the questions in the present case are both a lack of substantiality and the nature of the skill and labour to be protected’. There was no discussion of drawing clear boundaries between ideas and expressions, highlighting the Dichotomy’s diminished role in determining infringement cases.

The English approach to the relationship between the Dichotomy and technology was confirmed in Nova Productions v Mazooma Games [2007]. In this case, the claimant brought two sets of proceedings for copyright infringement concerning coin-operated games based upon the theme of pool. Jacob LJ dismissed the appeal by the claimant and held that ‘what was found to have inspired some aspects of the defendant’s game is just too general to amount to a substantial part of the claimant’s game’. In the judgment, like the approach taken in Navitaire v Easyjet Airlines [2004], Jacob LJ distinguished between general ideas such as the concept of a game, the taking of which would not amount to infringement, and detailed ideas whose taking could constitute infringement. Therefore, Jacob LJ used the substantiality test to determine the extent to which the idea of the game had been copied. From the structure of the judgment the Dichotomy is dealt with as an ex post characterisation which sealed the reasoning of a conclusion that had been reached by different means.

Most recently, Arnold J in SAS Institute v World Programming Ltd [2010] referred to the ECJ the question of where to draw the line between ideas and expressions in relation to software. In this case, the defendants developed the World Programming System to provide alternative software which enabled the execution of programs written in the SAS programming language. The defendants did not copy the source code for the program and so the courts had to consider a claim based on observing functionality only. In response, the ECJ indicated that, in judging infringement, there is no need to apply the Dichotomy rigidly and rather, as laid out in Infopaq International A/S V Dankse Dagblades Forening [2009], held that:

[T]he various parts of a work enjoy protection under Article 2(a) of [the Copyright Directive], provided they contain some of the elements which are the expression of the intellectual creation of the author of the work.

Arnold J in SAS Institute v World Programming Ltd [2010] accepted that copyright protection could exist beyond the source code – which in this context would strictly be the ‘expression’ – and also protect the design or the ‘structure, sequence and organisation of the program’. He held that one had to look at the skill and mental labour involved in devising the expression of the program. In this way, Arnold J accepted that applying copyright protection strictly to just the expression was unsuitable. Instead, he allowed scope for copyright protection to be determined in part in the mental labour expended in devising the expression: in other words, the ‘idea’.

SAS Institute v World Programming Ltd [2010] is further evidence that the Dichotomy’s applicability in English law has been limited to merely perpetuating the fundamental principle that ideas should not be protected, but the emergence of computer software has meant the courts have had to ease even this most basic principle. It is clear the courts are trying to avoid an outright concession that ideas should be protected, opting instead to rely on the traditional approach of evaluating the skill and labour instead of the Dichotomy.


As well as non-traditional works such as computer programs, this move away from the Dichotomy has also been seen in recent cases involving traditional works. Examples are Designers Guild Ltd v Russell Williams (Textiles) Ltd [2000] and Baigent v The Random House Group Ltd [2007], where the courts have held that if an idea has become ‘sufficiently detailed’ the courts will agree that it is protected by copyright to avoid ‘non-literal’ copying. 

While the requirement is that ideas still be ‘expressed’, it can be seen that the courts at least appreciate the validity of trying to protect the underlying idea – a direct violation of the requirements of the Dichotomy.  This qualitative approach has served to continually blur the lines between ideas and expressions and undermined the Dichotomy to the extent that it has little remaining influence in English law.

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Tagged: Commercial Law, Courts, European Union, IP, Intellectual Property, The Judiciary

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