If a game has models, textures, music from other games (i.e. copyrighted material), it is obviously illegal to distribute that game. If the author of the illegal game (say person A) sends the game to someone to play (say person B), for free if it makes any difference, and person B contacts the original authors, will person A get sued or just asked to stop? Can they prove that those resources were sent by person A at all?

Also, is there something that person A could do to mitigate the repercussions? Like putting in a disclaimer like "I do not claim to own any of the material in this game" (I've seen that in Youtube videos sometimes).

25 minutes ago, InfiniteLoop123 said:

 will person A get sued or just asked to stop?

There's no single answer. Each company can take different actions regarding their properties.

Some original authors sending a cease and desist request, asking person A to stop any further development and making the game unavailable. Another way is to ask the resulting game to be non-profit. This is seen as more community friendly . I recall Sega did something similar for Sonic clone games.

33 minutes ago, InfiniteLoop123 said:

Can they prove that those resources were sent by person A at all?

These things rarely go to court, so it's not a case for "proving". Also, this requires cooperation from person B, the only one - except for person A - that knows the game exists, as I understand what you said. Companies would probably go the cease and desist route first, which is enough in most cases.

Youtube videos are a different matter, as they're not competing with the product (videos and games are not the same thing, obviously). To a certain extent, Yotube videos are more in line with fair use, though there is discussion if this is valid or not, as the videos can be monetized.

That sounds fair. Thanks a ton TerraSkilll for taking the time.

The best answer is that this is a creative industry, you should be creative and not take other people's stuff without permission.

The much harder answer is that when you take things, even simple thematic things that are probably legal to take, you enter a gray area.  There are things that are completely okay and are standard scenes and tropes. There are other things that are clearly illegal.  But there also stuff in the middle that isn't clearly legal, but also isn't clearly illegal.

At that point it mostly becomes about risk management. 

A company may discover it, or they may not.  A company may discover it and decide the infringements are small enough that they take no action. Or they might take action, which may be anything from an email to a C&D order to a full lawsuit. The company may even quietly encourage it when the project is small and not interfering with anything, but when it grows and becomes popular suddenly issue takedown demands. The risk can be enormous, up to and including killing the product or losing property or even bankrupting the infringer.

The oft-given analogy is like speeding on a highway. Any speeding is illegal and a small percentage will get caught. The more flagrant the offense the more risk of being caught and the more the penalty increases. A few people will recommend speeding a little bit because you probably won't get caught and the penalty is usually small. A small group will recommend you ignore it completely because that group can afford the cost of a speeding ticket and don't particularly care about the safety and welfare of others.  But the only right answer is to recommend people follow the speed limit and obey the law.

IANAL, but as I understand it:

At the far end of the spectrum, if you make a fan game with ripped off assets, compile it without any information identifying you, upload it on a VPN / in a coffee shop, and don't use your name, it becomes very difficult for anyone to even identify who it is who is doing the infringing (that's assuming you don't go mouthing off on forums about it, logging in from your home IP etc). Think of it like committing a murder.

On the other hand, the moment you start trying to make money off such an enterprise (or even advertise), it becomes much harder, because there is usually a trail leading to the beneficiary. Added to this, once informed, legit 'publishers' / markets / payment processors won't usually want to touch stuff like this because of legal risks to themselves.

There is also the issue that in some jurisdictions they don't have the same IP laws as 'insert your country of origin'. Some are very lax about it, and won't give a hoot (compare say, US and China). So there can be international wranglings involved .. where is the game distributed from / to, where are the servers, payment processors?

Where is the development company based (developers in Norway, Vietnam, China provide work for a company in British Virgin Islands, selling to Asia, through a Chinese market using a European payment processor and the copyright holder is from the US, whose laws apply and where do you take them to court?) As you can guess it is also a potential nightmare for copyright holders to take action, it is easier for big companies with legal departments to protect their IP than small players.

Aside from deliberately infringing, there can also be accidental problems, which can affect even legit developers. If you contract out some artwork from a guy in China and he assures you (and signs paperwork) that it is all legit, and you later find he's ripped off someone else, you can still get sued. So as a developer you need to be super careful where you get all your assets, credit them if necessary, operate as some kind of limited liability company, and still get lots of insurance in case the worst happens (not to mention patent trolls etc).

19 hours ago, InfiniteLoop123 said:

Like putting in a disclaimer like "I do not claim to own any of the material in this game" (I've seen that in Youtube videos sometimes).

This is the same as doing a rain dance with a voodoo doll. It's actually worse than nothing as you're admitting guilt. 

19 hours ago, InfiniteLoop123 said:

will person A get sued or just asked to stop?

Depends how aggressive the owner of the stolen property is. Could be either, or neither, or both. 

On 2017-11-18 at 6:29 PM, TerraSkilll said:

There's no single answer. Each company can take different actions regarding their properties.

Some original authors sending a cease and desist request, asking person A to stop any further development and making the game unavailable. Another way is to ask the resulting game to be non-profit. This is seen as more community friendly . I recall Sega did something similar for Sonic clone games.

These things rarely go to court, so it's not a case for "proving". Also, this requires cooperation from person B, the only one - except for person A - that knows the game exists, as I understand what you said. Companies would probably go the cease and desist route first, which is enough in most cases.

Youtube videos are a different matter, as they're not competing with the product (videos and games are not the same thing, obviously). To a certain extent, Yotube videos are more in line with fair use, though there is discussion if this is valid or not, as the videos can be monetized.

Nintendo taking it into court or shuting down as fast as game gets attention, 

On 11/19/2017 at 12:31 PM, Hodgman said:

This is the same as doing a rain dance with a voodoo doll. It's actually worse than nothing as you're admitting guilt. 

I did some research and it indeed seems like putting a disclaimer is totally useless

What would be beneficial about it?  It says "I'm probably committing copyright infringement, at least a civil infraction and possibly also a criminal violation.  Somehow by telling you this I'm hoping nobody will take me to court, even though I just confessed to the world."

As suggested above, not only does not not help you, it hurts if they want to enforce it because you've already admitted you know you're infringing.  In the US that opens the door to triple damages. The law has a relatively small penalty if you accidentally violate it, but by declaring it up front you're open to much larger penalties. The thing is unlikely to ever reach court, as the admission of guilt means your lawyer will tell you to give in to basically whatever demands they want.

If you commercialize the game, you will have problems if it contains unauthorized material. You won't have any problem if you keep it for yourself or share it with friends.