Yeah, I'm just pointing that bit out because Dienstvertrag ("service contract", i.e. charging per hour) is a type of contract you might use to hire a freelancer

Yeah, I'm just pointing that bit out because Dienstvertrag ("service contract", i.e. charging per hour) is a type of contract you might use to hire a freelancer (the other one is Werkvertrag, "work contract", i.e. charging for a specific work with predefined requirements). As a former freelancer my first read of that line would have been that it also includes (sub-)contractors, which it of course doesn't. I don't know whether most business people are aware of §69b at all but in my experience many people just hire freelancers without a specific copyright arrangement and are then deeply surprised when they find out they don't actually own the project they paid the freelancer to create for them.