I'd like to know if it's legal to remove the footer copyright from a website theme, in this specific case a Wordpress theme.
I've modified the header and the menu, created a logo for the site and put it in the header. I've also modified part of the CSS. I'd like to put a sign of my work in the page but I was wondering if I can delete the © creator_name from the footer and leave only my one.
Site owner has paid for having this theme and then passed it to me to modify it, it's not a free one.