Keith Hoyt is Harvey's long-time friend. He is a businessman with a gambling and drinking problem who Harvey owes a favor.
In All In, after giving a keynote speech at a clean energy conference, Keith ends up playing in a high-stakes poker game after a drink too many in Atlantic City. Needing the money, he puts up his $30M company as collateral on a napkin contract to borrow $3 million from Thomas Walsh. With Harvey's help, though, they win it back,