Ultra Petroleum (UPL +7.1%) led a rebound by U.S. natural gas producers as nat gas prices rose for a third straight day; the New York benchmark is up 30% since April 19. UPL’s reserves are 96% gas, and the fuel accounts for ~97% of production; other stock winners included COG +5.4%, RRC +4.5%, SWN +4.1%. Contrast: UNG +7.5% in two days, USO -1.5%.