First of all, I strongly suggest you take a look at threads in this vein:
Second, I’d like to say that I am not a lawyer (and most of the people who will be replying to you are not lawyers) so take anything said here with a HUGE grain of salt: nothing you read on here constitutes as actual, actionable legal advice.
That being said, there are two issues at hand here: what is “legal” and what is accepted by Hosted Games/Choice of Games LLC.
“Legal” deals with what constitutes copyright and trademark infringement, and there is no real way to answer your question without knowing the copyright laws of the country you’re writing in as well as evaluating each video game/real-life reference you make in a case-by-case basis. There are a lot of factors at play in this, and how you use the reference is just as important as what reference you’re making.
For example, I was recently informed that I couldn’t reference Mickey Mouse in my novel because he’s a trademarked character by Disney. So, using his name and likeness without permission could run me into legal issues, regardless of the context he appears in.
But you could potentially reference your character eating at McDonald’s–BUT if you make up a fake restaurant with “golden arches” that isn’t McDonald’s (because the golden arches are trademarked), you’d get into trouble.
There are times when you can reference a trademarked product like Coca-Cola so long as you:
- don’t disparage or defame the product (“I drank Coca-Cola and now I have cancer!”)
- don’t infringe on its right to sell its product (you are not trying to sell Coca-Cola so this doesn’t really apply)
- don’t dilute the brand/trademark (using a brand name generically, like “Hand me a Kleenex” instead of “hand me a tissue,” implying all tissues are Kleenex-brand)
But! This is very, very tricky territory and every trademarked thing you mention must be evaluated on an individual basis!
Organizations can be just as tricky (or aggressive) with protecting their names, so if you reference Apple, you’d better make sure it’s in a way that could never be interpreted as negative for the company in any way. (The only character who uses Apple products is an asshole, etc.)
I strongly recommend just making up your own products, brands, and organizations, especially if they serve an important purpose in the story. If you want to talk about your characters going on an adventure tracking down a lost Amazon product, protect yourself and just use another word like Nile! (Unless that, of course, is also a real company.)
When it comes to referencing individual people… I would exercise extreme caution or just not do it at all. People usually own their own likenesses, so talking about them in a product that earns money is just a territory you don’t want to get into unless they’re a figure so far in the past they’re just commonly-referenced to, like Plato or Genghis Khan.
This borders close to plagiarism: please refer to the above inspiration vs. plagiarism thread. My blanket advice is to not do it. Use as inspiration but never “make use” of something that belongs to a preexisting property: it’s just not worth the risk!
Finally: what you think constitutes copyright infringement or not is one thing. You might follow the “letter of the law” in your country when it comes to these things. But I also want to stress that this may also differ from Hosted Games’ company standards, and they are fully in their right to accept, scrutinize, or reject references in your game based on their internal content review and policies. So just because you may think you’re in the legal right, doesn’t mean you’re always entitled to keep those things in anyway! Just as a word to the wise.
Not in the US (at least for books). I assume the same is true for IF and gamebooks: you can reference a song title in your prose (“she was bopping her head to Since U Been Gone by Kelly Clarkson”) but you can’t print lyrics, even one line, without permission from the copyright holder of those lyrics.
Unless the song is from before 1923 (again, US only), you must seek the permission of the copyright holder, who can deny you, make you pay a fee to use the lyric, or what have you.