A good example Jo probably is familiar is (ironically) Monopoly. In Brazil a Estrela, a Brazilian company, used to have a partnership with Hasbro and sell Monopoly as “Banco Imobiliário”. When Hasbro decided to get rid of the middleman and sell Monopoly themselves so Estrela rewrote the rules and
Fun fact, you can’t trademark the rules of a game, you can trademark the name, the logo and even all the text in it including the rules text but anyone can make a game that plays exactly the same as long said person use different wording for the rules.
'Eh, they started it with 'Orcs are Black people' and such nonsense, let them burn. See how they go when the fans they hate so much no longer support them, there are countless other systems out there anyway and once again, looking forward to seeing what the collaboration of companies produces.
My group plans to continue to play DnD, because we love the game and won't let anything stop us; Hasbro can forget about getting a penny from us though. 5etools site gives us all the info we need, and we won't be buying the books.