It's a $200m a year benefit based on what the refinery paid last year for the credits . The article used a jump in the stock price to say Icahn made $500M, but that's not really true because

1) Stock prices go up for many reasons 2) Icahn didn't sell to monetize in that gain and hasn't sold yet. And likely wasn't going to sell even if RIN reform passed. 3) Now that he's resigned and the odds of passing any RIN reform is virtually zero, the refinery's stock has zero RIN value in it.

I say it's trivial because $200m a year on a $17B portfolio is barely 0.1% a year. His deal-making efforts are worth many times that, at least 10% a year. So why get tied up in a mud fight with a pig over a scrap of a morsel?