You can look at this as trading. Anyway, I was reading a book where backing poker players was mentioned the backer taking 75%. I thought that was a bit too much so I looked it up:
https://www.pokernews.com/news/2012…s-insight-into-the-world-of-staking-13579.htm
“What is a standard backing deal?
A standard backing deal is fifty-fifty with make-up.