From copyrightservice.co.uk:
1. Is a logo subject to copyright?
Yes. A logo that includes artistic or design elements, (i.e. not just the name on its own), is legally regarded as being a work of artistic creation and therefore will be protected under copyright law.
Copyright protects the logo as an artistic work. As copyright is an automatic international right, it therefore follows that, (other than activities specified under fair dealing rules), unauthorised copying of that logo would be an infringement.
2. Could a trademark also apply?
This is possible. As the name suggests, a trademark can be applied to the logo as it is an identifying mark of the brand identity. Registered trademarks are applied for within a particular country or region and typically within a trading sector. A trademark will only cover the mark within that region or trading sector.
If you are interested in a trademark, you should contact a trademark attorney or your national patent or trademark office for further details.
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It belongs to the company, they paid money for someone to design it for them. Using it without permission is tantamount to theft. The law isn't in question, the only question is whether it'll save them money in the long run to sue somebody about it.
If you want an example, imagine LFS suddenly added a Ferrari without permission from the company. Ferrari fans would be very interested, so the game would pick up a lot of Ferrari followers who bought the game for that. That's money being made on the Ferrari name, despite nobody at the company saying yes they could do it.
Does Ferrari make anything from this arrangement? No.
Do they lose anything? Possibly. A Ferrari fan with a simulator already is less likely to buy a new simulator that Ferrari have given permission and spent money helping to develop. Like Ferrari Challenge, since it's the only one I can think of. The quality of the product is irrelevant in this case, but may have connotations elsewhere. Why would I buy that when my favourite Ferrari was already in a game I have?
The other thing is that Ferrari would have no rights to say "this element is wrong". You could have the Enzo outrun by the XFG if you wanted, and they couldn't do anything. That would be creating a negative brand image, which is probably also equal to slander.
On a small scale, a handful of copies, it's not such a big deal. The skins, for example, aren't a big moneymaking scheme and are likely to only go to a couple of people. To You wouldn't even get the cost of a single lawyer for the total amount made. But LFS has a fairly large global fanbase. It's not actively marketed, but it does continue to pick up new users all the time. It's not Forza / Gran Turismo big, but it's healthy.
So in this case it would be prudent for Ferrari to stop the LFS team selling their product because they could be losing money. Not only that, having their name on a non-Ferrari car potentially being driven by a useless driver means when people see it, they equate it with the Ferrari name. And that's not necessarily a good thing.
What a long post. I rest my case, Your Honour.