royal
The latest kerfuffle between Harry and Megan and the Queen has been presented as an argument about their right to use the word royal in association with themselves and their various projects, some commercial and some charitable. The Queen has forbidden it. Harry and Megan have said that she has no claim to own the word royal and that, while they will abide by her decision, they dispute it.
I think there is a confusion here. The people who clearly own words are the ones who trademark a word. And it is accepted that no one can trademark a word that is already in general use. So no one can trademark the word royal which has a long history in general use with many different meanings. But what the Sussex couple have attempted to trademark is their proposed brand Sussex Royal. That is a different kettle of fish.
What the Queen has always said is that no working member of the royal family should derive personal benefit from their position as a member of the royal family, and she has now said that that applies to non-working members of the royal family as well. That seems fair.