Shares of U.S. refiners pared gains late Tuesday after President Donald Trump’s administration denied that it was considering a proposal to change biofuel blending rules. Billionaire investor Carl Icahn and the leading U.S. biofuel trade group struck a deal to revamp a law that mandates oil refiners to either blend petroleum-based fuels with ethanol and biodiesel, or buy blending credits called RINs, according to people familiar with the agreement, and the shares rose earlier in the day on the news. They slipped after the White House said there was no deal. Merchant refiners including Icahn’s CVR Refining and Valero Energy Corp . would benefit from a deal. Gasoline blenders that operate fuel stations such as Casey’s General Stores Inc. and Murphy USA Inc. would have to shoulder the costs. Ethanol blending credits for 2017 compliance fell by nearly 35 percent Tuesday to 30 cents each, the lowest on record […]