Sometimes it starts with nifty "cease-and-desist" letter with a delay to comply; if you don't comply then the publisher gets nastier. If the publisher really feels like it, you can get into a criminal suit fairly quickly: you should get the visit of law officials who will give you a seizure notice and take away all your computers, backup CDs, etc. You will then be summed up to appear before a judge for a summary where the publisher will exhibit its case for breach of copyright along with its claim for damages. It usually goes downhill after that.

Let's check the law (Title 17, ch. 1, section 107):

Quote:Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include—

(1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;

(2) the nature of the copyrighted work;

(3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and

(4) the effect of the use upon the potential market for or value of the copyrighted work.


The fact that a work is unpublished shall not itself bar a finding of fair use if such finding is made upon consideration of all the above factors.

It's a tossup as to whether you have to meet all qualifications or just one. "The nature of the copyrighted work": well, for Star Wars and LotR, there are movies, books, and video games, so you'd probably fail on that count--it's almost a replacement product. "The amount and substantiality" is a twofold qualification: if you use a two-second clip from Star Wars, it's probably not infringing (though there are extreme mixed CDs that have been sued for using 2-second clips from hundreds of copyrighted works without licenses; US copyright law is implemented badly, in the same way that someone who's missing four limbs and a lung is doing rather badly). And if you're taking a number of characters from the original, copyrighted work, that would probably be infringement. (Unless, of course, you used only the most minor characters and took them away from the main storyline far enough. But you'd still be using the same world...that's illegal.)

As for the effect on the market value for the copyrighted work...if you're not selling it, it can still have an effect. If I made a freeware game that was similar in many regards to Doom III and had equivalent graphics and features, that would impact Doom III's market share. On the other hand, so would Unreal III. So if id could show that your product takes content from the Doom series AND that it's losing market share to you, then it has a powerful case and can seek damages.

So what if you have a game that doesn't even compete but takes content? It's probably still illegal--you'd want to talk to a lawyer--but you probably won't get sued over it. You might receive a cease-and-desist order eventually, or perhaps the copyright holder will see your game as a marketing scheme and perhaps try to take it over for a pittance, threatening lawsuits if you don't comply. Or, since your work is illegal (for distribution; you could make a thousand Star Wars games legally if you don't distribute them), they can simply steal the content, put a multimillion dollar budget behind it, and make something that leaves your game in the dust.

If, on the other hand, you don't squat on someone's trademark and only borrow a few world details--the Force and lightsabers, perhaps with different names--you should get out without trouble.