Avalon Hill - permission needed?

I know it wouldn’t be “public domain” in the usual sense, as they still retain full IP rights, but it seems like many AH games have been added here and I’m wondering if there’s some kind of assumed permission being that the games are all out-of-print. Or are people still contacting someone at whatever remains of AH to get permission? And if so, who/what/where is the contact, as I’d like to add a module for an old AH game?

Thanks much.