If a refiner produces RBOB and sends it down a proprietary line to his own terminal where it is blended with ethanol, is the refiner required to register as an oxygenate blender for this terminal oxygenate blending operation?

Yes. (7/1/94)

This question and answer was posted at Consolidated List of Reformulated Gasoline and Anti-Dumping Questions and Answers: July 1, 1994 through November 10, 1997 (pdf) (18.2 MB, July 2003, EPA420-R-03-009).