premise: Nate Diaz refused to ever sign with the UFC.
hypothesis: Nathan Donald `` Nate '' Diaz ( born April 16 , 1985 ) is an American professional mixed martial artist currently competing for the Ultimate Fighting Championship ( UFC ) . Prior to signing with the UFC , Diaz competed in World Extreme Cagefighting , Strikeforce , and Pancrase . Diaz is also tied with Joe Lauzon for the most UFC bonus awards , with 15 in total . Nicholas Robert `` Nick '' Diaz ( born August 2 , 1983 ) is an American professional mixed martial artist who is currently signed with the Ultimate Fighting Championship ( UFC ) .