Copying another person's work is a legal issue as well as a philosophical one. Yet, copyright law in the United States is intentionally vague, so as to reflect the real uncertainty between theft and inspiration. "The standard for copyright infringement in U.S. doctrine is 'substantial similarity,'" Greg Boyd, an IP lawyer for Davis & Gilbert LLP, said.
"A lot of people upon hearing 'substantially similar,' will say 'what a horrible rule,' but it is intentionally vague in order to be powerful and flexible. If you really sit around and think about it, it's difficult to come up with something better."
Copyright law does not protect ideas, per se, but the way in which an idea has been fixed in a tangible medium. "If I say I have an idea for a game mechanic and you think that's great and go out and make a game out of that mechanic you might have violated some things but you haven't violated copyright law," Boyd said.
"I hadn't fixed my idea in a tangible medium, I hadn't written it down or coded it. After things are in the code form, then it's in a tangible medium."
For these reasons, litigating a copyright infringement case can be especially difficult, because you not only have to demonstrate egregious similarities between two games but show how their specific expression in compiled code is substantially similar.
With social and mobile games, changing a toad into a bat or a jewel into a piece of sports equipment can seem like a substantial difference, or at least blur the distinction enough to make it hard to make a ruling.
Another complication is that the differences in copyright law from country to country make it difficult and costly to pursue a lawsuit against overseas developers.
"We've seen a lot of copycatting, specifically in Russia there was a direct clone of [DJ City]," Brian Cho, director of business development for Booyah Games, said. "In Asia there were also a lot of copycat games, especially in Korea and Japan, but those weren't on any of the platforms that we were on."
"I think we would definitely have taken a hit if there was a copy of our game on Facebook, we would definitely have taken action there. But because it was in developing countries that we weren't planning on going to anyway, we couldn't necessarily take any steps to protect ourselves as a small, startup company."
Even with the law on your side, it can be lucrative enough for developers in countries outside the U.S. to run a game that infringes on copyright for a short period of time, making it all but impossible to stamp out completely. "Income disparities between the U.S. and overseas contribute to it," Boyd said. "If you're going to be a pirate in a lot of countries for just a matter of days or even a few weeks -- that can be hugely profitable, even if you know that eventually you'll be taken down."
Having a common platform like Facebook or Apple's App Store can be helpful, in that it at least offers a common authority for appeal. "Facebook will absolutely comply with U.S. law and in some cases they've intervened ahead of a court order or a threat of legal action," Harbin said. "They have a legal team there and they understand copyright law and know that life will be easier if they can take some action in advance."
"In one instance, there was a competitor who hadn't completely copied one of our games but they were directly referencing elements of our proprietary language in their advertising. They were targeting our users and insinuating that we were responsible for the title they were advertising. It was a little bit of a gray area but the legal team realized that if we sued them we probably would have won, and so [Facebook] suspended all those ads."
Another area of vagueness with game copyright law comes with the distinction between a game's code and the creative end result produced by it. A company might take a specific portion of someone's A.I. code and use it in a game that looks and plays nothing like the original. Or else, a developer might copy the same patterns of A.I. as closely as possible but write their own unique code to do it. Might these be areas of conflict unique to video games, for which U.S. copyright law might need to be modernized?
"It's a great question, and it's definitely a great policy-level question, but you have to consider the complexity of the issue," Boyd said. "You can't make special rules for one artistic medium. Think of the First Amendment. It protects movies just like it protects games and books. We have to have copyright law that does the same thing. If you start doing specialized carveouts, it's a dangerous path. You can do just as much harm as you can good."
In practice, then, defending one's creative work and determining what constitutes infringement and what doesn't is a slow and murky process that must bring substantial similarity to bear on both the creative product and the technical code in which it's fixed.
"We usually just look at the genre, the mechanics of the game, and then we deep dive on how closely they've copied the game," Cho said. "There are quantitative ways to see what percentage of our game they've copied, and if it's over a certain percent we'll take legal action. Having those figures really helps our case."