This is what's keeping me from working on my own "John Carter of Mars" game. The books (at least the first 5-6) are public domain, but Edgar Rice Burroughs, in

This is what's keeping me from working on my own "John Carter of Mars" game. The books (at least the first 5-6) are public domain, but Edgar Rice Burroughs, inc has John Carter, Dejah Thoris, etc., all trademarked, and can continue that indefinitely. I don't think it would be a slam dunk legal case, but it's enough to discourage me from trying (I've heard they are litigious).