A US District Court judge has ruled that an iPhone Tetris clone called Mino is infringing on the copyright of the Tetris Company, which could have repurcussions on copycat games elsewhere.

Back in May 2009, a particularly bold Tetris copy called Mino was released on the iPhone. In August of that year, the Tetris Company caught wind of the app and sent takedown notices -- pursuant to the Digital Millennium Copyright Act -- to Apple. The app was quickly removed.

Mino developer Xio sent two counter-notifications to Apple. The iPhone creator then informed Tetris Holding that the games would have to be reinstated unless it filed a lawsuit. That litigation was brought forward in December 2009.


Xio readily admitted that Mino purposefully and deliberately copied from Tetris, and turns the basic block-dropping concept into a multiplayer game. The developer even fessed up to downloading the official Tetris for iPhone (published by EA), for research.

However, the copy creator also said that when it was refused a license from Tetris Holding, it meticulously researched intellectual property law to see how to make a copy of the puzzler that would not included any legally-protected elements.

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Brazen videogame clones generally avoid legal trouble because the functionality of the game -- the rules, the mechanics and the design -- are not protected in the same way as the artwork, music and source code.

It is possible to patent a piece of game design -- Sega holds the patent on the big floaty arrow in Crazy Taxi, for example, and Microsoft has exclusive rights to the skilful driving system in Project Gotham Racing -- but patents have to be applied for, while copyright is automatically awarded.


The US District Court for the District of New Jersey didn't exactly agree with Xio's defence that the iPhone clone only borrowed ideas that were not protected.

She agreed that "the game mechanics and the rules are not entitled to protection," but said "this principle does not mean, and cannot mean, that any and all expression related to a game rule or game function is unprotectable. Such an exception to copyright would likely swallow any protection one could possibly have; almost all expressive elements of a game are related in some way to the rules and functions of game play."

Judge Freda Wolfson declared that "Tetris Holding is as entitled to copyright protection for the way in which it chooses to express game rules or game play as one would be to the way in which one chooses to express an idea."

Alex Tutty, a lawyer at Sheridans who specialises in games and digital media, explained to Wired.co.uk that the ruling will not change US or international law, but will help clarify the link between non-protectable elements (design, mechanics) and protectable elements (art, music). "Xio stated that it had copied the visual expression of Tetris but argued that this wholesale copying was allowed as it believed that the visual expression of Tetris was a result of the underlying idea and functionality," says Tutty. "This is an argument which is often raised by those accused of cloning. The court disagreed."

So Xio would have been legally entitled "to release a puzzle game where a user manipulates blocks to form lines which disappear," but when it copied the way that idea is expressed, by using the same style of pieces, the same dimensions of the playing field and the same manner in which the pieces move and rotate, the judge ruled that Mino is infringing upon copyright. "The importance of this is that companies accused of cloning have defended their actions by stating that [mechanics and artistic elements] are inseparably linked. This is not the case in the US and it is not the case in England and as a result those who feel that their game has been cloned or unfairly copied can take steps to stop it," Tutty explains.


Tutty says that the Tetris ruling will serve "as an example to developers that there is protection against clones and that they are not powerless to do anything. It also serves as a warning to those producing clones that the spurious arguments previously raised are not effective and that cloning or very closely copying other games can result in expensive legal fees of a weak (if not indefensible) position."

It could have implications for the Triple Town developer Spry Fox's copyright infringement suit against 6Waves Lolapps' Yeti Town, and other borrowings.

Image: Nintendo Gameboy / <a rel="cc:attributionURL" href="http://www.flickr.com/photos/wwarby/">William Warby</a> / <a rel="xh:license license" href="http://creativecommons.org/licenses/by/2.0/">CC BY 2.0</a>