What I've read is 1-4% royalty on sales. It isn't backed by anything though. Royalties are nice so long as the economy is doing fine. The US looks like it is headed into a recession. I like the dividend if it is sustainable.
Seems like a gamble on companies earnings growing and thus growing the royalty payment. The investment not being backed by anything, in addition to it siphoning off cash from the biz, seems sketchy to me.