On imitation and innovation in the games sector: From Pong to Ridiculous Fishing

14 November 2014

Die Entwicklung von Computerspielen bewegte sich schon immer zwischen Imitation und Innovation. Schon das erste wirtschaftlich erfolgreiche Spiel „Pong“ war Gegenstand eines Konflikts: Atari als Publisher wurde vorgeworfen, das Spielkonzept von Magnavox‘ „Odyssey“ gestohlen zu haben. In der Folge hat sich in einer Reihe von ähnlichen Fälle gezeigt, dass Computerspiele urheberrechtlich kaum vor Imitation zu schützen sind. Das Urheberrecht schützt nur die konkrete Ausgestaltung einer Idee, nicht die Idee selbst. Der Kern eines Spiels aber ist ein abstraktes Regelsystem, das eher der ungeschützten Idee entspricht als dem geschützten Werk.
Wie aber gehen Spiele-Entwickler selbst mit dieser Frage um? Ziehen sie eine klare Linie zwischen akzeptierter Inspiration und geächteter Imitation? Befunde einer Diskursanalyse von Sarah Herweg im Rahmen des Projekt «Zirkulation von Kulturgütern» zeigen, dass Entwickler die Unterscheidung zwischen freier Idee und geschützter Ausgestaltung auch bei Spielen anwenden: Ideen – also Spielmechaniken – sollen frei bleiben, wohingegen ganze Spiele gegen Plagiate als geschützt gelten sollen. Darüber hinaus artikulieren die Entwickler Handlungserwartungen, die gegenseitige Koordination im Graubereich zwischen diesen Polen ermöglichen können. Diese Konventionen werden allerdings nicht von allen Entwicklern geteilt. Es muss daher eine Frage weiterer Forschung sein, inwieweit die hier artikulierten informellen Normen in verschiedenen Teilbereichen der Games-Branche geteilt und angewendet werden.

Von Lies van Roessel und Sarah Herweg.

Imitation in computer games has been an issue since the beginning of the medium. Even the launch of the first commercially successful game, Pong, brought two developers into conflict. In 1972, console manufacturer Magnavox accused Atari of having stolen the idea and technology for electronic ping-pong on a television screen from Magnavox employee Ralph Baer (Kent, 2001, p. 46). This case did not make it into court, as Atari bought a licence to exploit Pong for many years to come. In turn, the enormous popularity of Pong caught the attention of competitors, and it turned out to be appeared difficult to protect Pong as intellectual property. This spurred many Pong imitations:

„No sooner had Pong become the hottest innovation in amusement machines than dozens of potential competitors began studying it. (…) Bushnell had entered into an industry in which success spawned imitation, and everybody considered Pong a success, with Pong machines earning $200 per week. There was no way to stop companies from copying it.“ ﴾Kent, 2001, p 60﴿

Many similar cases followed. These involved developers and publishers accusing other developers or publishers of copying their work, and of infringing the original creator’s copyright. For instance, in 1988, Data East sued developer Epyx for copying their game Karate Champ, and in 2009 Xio was incriminated of making a Tetris clone. Not all disputes made it into court. Recently, there also have been many cases of alleged cloning. Some of them have been covered by the media, such as Threes and Flappy Bird, but some of them are also less well known, such as …and then it rained by Berlin-based indie studio Megagon Industries, who claim their game was cloned four times.

It’s remarkable that some of the above mentioned developers have stood on both sides of the fence. For instance, Atari – after the conflict around Pong – accused Amusement World of imitating their game Asteroids. Also, former plaintiff Data East was accused of copying Capcom’s Streetfighter 2 (McArthur, 2013). In other words, it’s not always the same companies that are the alleged cloners or original creators. In some cases, for example, with Tetris, the plaintiff won the case; in many other cases, however, the defendant was deemed right.

Copyright for games?

This tendency to acquit defendants accused of copyright infringement, might have to do with the nature of copyright and its problematic application to games. To understand why this is problematic, it is necessary to look at the nature of copyright a little more closely.

Copyright law distinguishes between idea and expression. A work benefits from copyright protection as soon as it is written down, recorded, painted, thus fixed in any tangible medium of expression. However, the idea behind the expression stays in the public domain and remains unprotected (Herweg, 2014). Even for works such as books, movies or music it might be quite hard to define where to draw the line between idea and expression. If one wants to write a book, for example, about a clever private detective who solves crimes by means of logical reasoning, this idea can freely be used. However, if this person lives in London, wears a long coat and is helped by a doctor friend, the idea increasingly turns into a work or expression, which could infringe the copyright of the Sherlock Holmes stories. In other words, there is a fine line between a (free) idea and a (protected) work or expression.

For games this is even more complicated. Games are composed of many separate elements, most of which can be protected by intellectual property law. For instance, the hardware may be protected by a patent, source code is protected as software, and one can apply for a trademark for game titles and character names. For the graphic and audio elements, there is copyright protection. However, a unique part of games, which cannot be found in other audiovisual media, is the underlying rule-based system.

In academia, there has been a big debate about what sets games apart from other media (e.g. Aarseth,1997; Juul, 2001; Eskelinen, 2001). The question of the extent to which games are comparable to other audio-visual media has often been discussed. One of the conclusions was that games are by definition rule-based systems, with which the player always actively engages. This makes them inherently different from linear, non-interactive media such as films or books, in which the course of the story is fixed beforehand.

A simple example from the game chess might clarify this. What makes chess an interesting experience, are not the in-depth characters of the chess pieces or the adventures they experience but the interactions of players with a precisely balanced, rule-based system (and with each other). Changing the visual style of the chess pieces, for example, would not alter this experience completely. In other words, what defines chess as a game, rather than the audiovisual or story elements that are found in other media, is this rule based system, i.e. the possible moves affordances of the pieces, the actions that emerge from these affordances and the interplay between the actions.

Because players interact with the game system in a different manner each time they play, the experience is never fixed beforehand. Besides, the underlying rule system only truly reveals itself when one actually plays the game (one can hardly grasp it from pictures of the chess board). This makes the distinction that copyright draws between idea and (fixed) expression even harder. In the case of chess, an expression of the rules could be a written manual, but the rules could also be communicated orally or by a video. The ‘idea’ of chess rules can thus be expressed in many different ways. Moreover, in most current video games, the rules are usually not communicated explicitly upfront. Instead, in the process of playing, one gradually explores the rules of the game, as they are at first glance hidden behind the interface, graphics and audio. Some say this exploration and learning of the rules is actually one of the main pleasures of playing games (e.g. Koster, 2004).

Therefore, these rule-based systems could arguably be placed in the realm of (abstract) ideas rather than (concrete, fixed) expressions. Bruce Boyden describes it as follows in his article ‘Games and other Uncopyrightable Systems’: „Video games, despite being comprised of software, audiovisual elements, plots, graphics and characters, nevertheless have an uncopyrightable core: the actual play of the game“ (Boyden, 2011).

In the above-mentioned disputes between developers, it was often difficult to unravel the separate elements – of which, as argued above, some are and some are not protected. It is even harder to understand how exactly these elements relate to and influence each other. When, for instance, the rule based system is copied, but another graphical style was chosen, it is hard to say whether there was any copyright infringement. This applies even more so when a judge has to determine the facts without having played the game – and thereby without having interacted with the system – herself.

Imitation as genre building

One could argue that, due to this lack of protection of the essential rule system, copyright law for games should be extended to include this. However, the dichotomy between idea and expression in copyright is there for a reason. If ideas and concepts were protected, it might become difficult for game genres to develop. Genres have typically emerged out of one or multiple existing ideas that have been taken further. In many cases, these ideas were the mechanics, i.e. the rudimentary building blocks of rule-based systems. For instance, there wouldn’t be so many first person shooters out there, if it had been impossible to use Wolfenstein (or by earlier, less well-known examples) as an inspiration. Games scholar Jesper Juul depicts in his book A Casual Revolution an interesting evolution of so-called matching tile games (see figure 1). A certain degree of imitation is always necessary to bring a medium forward. Building upon good ideas and fine-tuning them is a healthy way for a sector to maintain itself and grow.

 A family tree of matching tile games (Juul, 2010)

Figure 1: A family tree of matching tile games (Juul, 2010)

Thus, extending copyright to apply to rule systems might have an undesired side effect – it actually could impede genre development.

Social norms and conventions

Taking a look at the legal side of this issue is interesting, however, law is not the only way to regulate things. There are also other ways a sector can structure itself. For instance, in some smaller industries it is shown that an unclear legal situation does not necessarily mean a lack of rules. Research into imitation and inspiration in the fields of stand-up comedy, cooking and magic, has yielded remarkable insights in this issue: when legislation does not suffice, informal norms and conventions are leveraged.

A similarity between the products made in these sectors and games, is that they rely on abstract ideas and concepts rather than on media expressions: jokes, recipes and tricks. Although in many respects these sectors are hardly comparable to the games sector, for instance, because they differ in size and are less dependent on digital technologies, it is nevertheless interesting to see how informal norms and conventions in these fields go beyond copyright or other legal intellectual property protection. In stand-up comedy, for example, some of the social norms are stricter than actual copyright legislation. The joke as idea is protected within the community of comedians, which includes sanctions for someone who crosses the line and steals an idea. Moreover, the protection applies for indefinite time, whereas copyright protection expires 70 years after the death of the author (Hofmann, Katzenbach and Münch, 2012). Thus, these rules are not prescribed by law, but by the shared community of professionals within the field.

The question thus rises whether there are comparable social norms and conventions within game development. As the games industry has grown tremendously in the last decades, it might be difficult to find norms that apply to the whole sector. Nevertheless, the branch association IGDA has made an attempt – over ten years ago – to write guidelines for developers to deal with intellectual-property-related issues. In their white paper, the IGDA acknowledges that a certain degree of imitation is totally accepted within the games industry. However, they also address the moral standards, since the law does not always provide clear-cut answers:

„One must avoid any outright stealing of other’s work. It is not fair to them and you would likely find yourself in trouble eventually.“ ﴾IGDA 2003, p 38﴿

Later on, they suggest:

„Even if you were only inspired by someone else’s work then consider giving them some credit.“ ﴾IGDA 2003, p 38﴿

IGDA’s formulation indicates a certain cautiousness. They don’t firmly claim that you’re breaking the law when as a developer you copy other developer’s work, but they speak to the ethical responsibility of the developers.

A discourse analysis of Ridiculous Fishing

An initial exploratory study on this topic was conducted by Sarah Herweg. She looked into the opinions and standpoints voiced by game developers about this issue, and looked for norms and conventions comparable to the ones existing among comedians and magicians. Do game developers have a common understanding of where to draw the line between acceptable inspiration and objectionable cloning? The findings show that in general game developers agree on the idea–expression dichotomy as it is made by copyright law: ideas in the form of core mechanics should remain freely available, whereas expressions are to be protected.

The research was done on Gamasutra, a popular game developers website, blog and forum. Two cases of alleged cloning were analysed: Ridiculous Fishing versus Ninja Fishing and The Sims Social versus The Ville. Here we will go further into the first case: the conflict between Utrecht-based indie developer Vlambeer (Ridiculous Fishing) and US-based studio Gamenauts (Ninja Fishing). To better understand the case, here we will provide a short overview of the situation.

In 2010, Vlambeer released the game Radical Fishing, a flash game in which the player is a fisherman whose aim it is to catch as many fish as possible and then to shoot these fishes from the air. After releasing the browser game, Vlambeer continued working – under the radar – on a more advanced iOS version of the game. Then, in 2011, American developer Gamenauts released their game Ninja Fishing, for iOS. Ninja Fishing was heavily inspired by Radical Fishing. Although Gamenauts had chosen a different theme (ninjas with knives rather than fishermen with guns), the gameplay was similar to a great extent, as the rules were largely similar. When Vlambeer heard about the planned release of Ninja Fishing, they contacted Gamenauts and asked them to postpone the launch of the game until Vlambeer had released their own iOS version of the game, called Ridiculous Fishing. However, Gamenauts did not respond to this request. As Vlambeer was aware of the fact that litigation would mean a small chance of success, they decided not to take any further action. In 2013, Vlambeer release Ridiculous Fishing and the game was an instant success. The game won the Apple Design Award in 2013.

Divided opinions

In her research, Herweg analysed and categorized seven articles and 247 comments on these articles from Gamasutra. She looked at the opinions of the commentators and how they justified the behaviour of one of the two parties. The opinions about the case were divided. Some condemned Gamenauts and accused them of cloning, whereas others asserted that Ninja Fishing had some innovative elements in comparison to Ridiculous Fishing, and therefore it was just inspired by it. Thus, the fine line between imitation and inspiration was not drawn in the same place by the whole Gamasutra community.

The readers on Gamasutra were very well aware of the difference between idea and expression in copyright legislation. Their comments reflected this dichotomy. Generally, the commentators agreed that anyone should be able to reuse core mechanics, whereas the wholesale copying of a game is a no-go. The following comment illustrates this:

„There is a certain granularity of copying that is acceptable: making a cartoon about a mouse is OK, but when you make him look exactly like the mouse, or give him the name Mickey Mouse, then that’s infringement. I think my argument that copyright should extend to game mechanics draws the line of granularity at copying a whole work of game design. I am most definitely against patenting or copyrighting individual mechanics. The difference I am trying to draw here is that we still need a free marketplace of ideas from which new games can grow, but protecting innovators against wholesale ripoffs is a good thing.“

In other words, if a developer, besides the core rule system, also copies fine-tuned elements like the so-called balancing and the interface design, it gets problematic. For instance, one of the commentators argued:

„My conscience won’t allow me to say I innovated a game by changing one thing and changing the art. (…) It was the core mechanics… The fishing, the concept, the weapons, the power ups. The combination into one complete, fun experience. That, is what was copied FIRST. And one change, in my mind, doesn’t cut it (pun intended).“

This reader thus claims that Gamenauts went too far in copying Ridiculous Fishing. It’s interesting that he does not refer to what is legally allowed, but rather speaks from what his conscience would allow him to do. This hints at the presence – at least for him – of other frames of reference than just the law.

While this quote deemed Vlambeer a victim, another comment saw this differently:

„Additionally, Ninja Fishing actually did include some innovations: the art style is different, and more mass market than the original Radical Fishing (which looks… ahem… shitty), and they included a slicing mechanic (which is lifted from Fruit Ninja and a number of other iOS games). These are small, but they are technically innovations.“

This person asserts that the small adjustments and the different visual style are enough to make Ninja Fishing into a new game. He refers to innovation as making small steps to improve or enrich things.

Informal norms

In the process of examining the Gamasutra comments, Herweg also searched for possible social norms that could provide guidelines for developers how to deal with such situations. Some comments offered suggestions for what Gamenauts could have done to ensure better conduct. For instance:

„I think contacting the original inspiring developers is a good first step. At least asking them what they think, if they are planning something to move on.“

In addition to asking the original developer for permission (or at least informing them), an explicit reference could also help:

„In the absence of copyright protection, what should game designers do? ALWAYS CREDIT YOUR GAME DESIGN INSPIRATIONS. Educate the public on the inspirations behind other games.“

Thus, Gamenauts could have given credit to Vlambeer, in order to stay on the right side of the (ethical) line. The suggestions offered here by the commentators hint at possible norms existing in the games sector, which could help guide behaviour in the case of uncertainty around copyright protection of the work. However, not many commentators provided these kinds of guidelines. Moreover, suggesting them does not necessarily mean that this is common practice or even that they themselves would act in such a way.


In sum, Gamasutra readers agree about the dichotomy reflected by copyright legislation: ideas such as core mechanics should be freely available for anyone to use, whereas fully developed existing games should be protected from plagiarism. They also agreed that when only the audio-visual elements are changed and the entire rule based system stays the same (a so-called reskin), this is in general not accepted. Every game should contain at least an improvement or addition with respect to the original game, not only in graphics, but also with regard to the underlying rule system.

However, the case of Ridiculous Fishing also shows that it is difficult to know where exactly to draw the line between reusing core mechanics and a wholesale copy of the rule system. At what point has one added or adjusted enough for it not be a clone anymore? This is a grey area in which disagreements can easily arise. When a developer finds herself in this grey zone, possible steps to take include asking the original developer for permission or explicitly referring to the source of inspiration.

However, it is hard to say whether the actual way developers handle this issue corresponds to the suggestions made by the Gamasutra readers. The people commenting are not Gamenauts or Vlambeer – and obviously in this case Gamenauts did not act according to the suggested guidelines. Hence, more research is needed to look at how developers are actually dealing with these situations: to what extent are these norms shared and acted upon? Moreover, the games industry is a huge sector, and chances are that different sub groups exist with different norms and conventions that are not necessarily shared among the games industry as a whole. For instance, indie developers are often mentioned as a distinct group within the games sector, and their conventions may differ from those of other game developers.

The case study described here is an initial study as part of a larger project at the HIIG into imitation and innovation in the games sector. The current research compares different subgroups of the industry in terms of their conventions on imitation and inspiration. By interviewing developers, we hope to find out whether the guidelines suggested on Gamasutra are actually shared and acted upon. Considering the many recent conflicts around imitation, more knowledge about how this is regulated – within the law but also outside the legal realm – is helpful.


Aarseth, Espen. Cybertext. Perspectives on Ergodic Literature. London and Baltimore: The John Hopkins University Press, 1997.

Boyden, Bruce E. ‚Games and Other Uncopyrightable Systems‘. In: Marquette University Law School Faculty Publications. January 1st 2011. Herweg, Sarah. Discourses on Imitation and Innovation in the Games Industry. Freie Universität Berlin, 2014 ﴾forthcoming﴿

Eskelinen, Markku. ‚The Gaming Situation‘ Game Studies 1:1. 2001. www.gamestudies.org/0101/eskelinen

Hofmann, Jeanette, Christian Katzenbach and Merlin Münch. ‚Kulturgütermärkte im Schatten des Urheberrechts – zur Pluralität praktizierter Regelungsformen‘. In: Aus Politik und Zeitgeschichte. 8 October 2012

IGDA. Intellectual Property Rights and the Video Games Industry. 2003 archives.igda.org/ipr/IGDA_IPRights_WhitePaper.pdf

Juul, Jesper. ‚Games Telling stories? – A brief note on games and narratives‘ Game Studies 1:1. 200. www.gamestudies.org/0101/juul-gts/

Juul, Jesper. A Casual Revolution. The MIT Press, 2010

Kent, Steven L. The Ultimate History of Video Games. New York: Three Rivers Press, 2001

Koster, Raph. A Theory of Fun for Game Design. O’Reilly Media, 2004

McArthur, Stephen C. ‚Clone Wars: The Five Most Important Cases Every Game Developer Should Know‘. Gamasutra, 2013 www.gamasutra.com/view/feature/187385/

Dieser Beitrag ist Teil der regelmäßig erscheinenden Blogartikel der Doktoranden des Alexander von Humboldt Institutes für Internet und Gesellschaft. Er spiegelt weder notwendigerweise noch ausschließlich die Meinung des Institutes wieder. Für mehr Informationen zu den Inhalten dieser Beiträge und den assoziierten Forschungsprojekten kontaktieren Sie bitte info@hiig.de.

Dieser Beitrag spiegelt die Meinung des Autors und weder notwendigerweise noch ausschließlich die Meinung des Institutes wider. Für mehr Informationen zu den Inhalten dieser Beiträge und den assoziierten Forschungsprojekten kontaktieren Sie bitte info@hiig.de

Weitere Artikel


Statusarbeit in der Datengesellschaft: Überkapital und Hyperindividualisierung

Ob Kinderbetreuung, Kredite oder Konsumgüter: Ratings, Scores und der digitale Fußabdruck führen zu neuen Klassifikationen. Diese zunehmende Quantifizierung des Sozialen begründet neue Formen von Statusgewinn und -verlust, die Marion Fourcade...

„Es geht um Menschenwürde und Autonomie“

Privatsphäre und Datenschutz werden derzeit so intensiv debattiert wie noch nie. Im Gespräch erzählt Frederike Kaltheuner von der Bürgerrechtsorganisation Privacy International, warum diese beiden Begriffe so fundamental wichtig für uns...

Enterprise Social Networks: Empowerment oder Kontrolle?

Im Zuge der Digitalisierung des Arbeitsplatzes führen zahlreiche Unternehmen digitale Plattformen ein, die die MitarbeiterInnenbeteiligung stärken sollen. Die Implikationen von Social Media für die Bedeutung von politischem Engagement und Partizipation...