First issued in 1979 as required by section 203(c)(1) of the Petroleum Marketing Practices Act and last revised in 2011, the Automotive Fuel Ratings, Certification, and Posting Rule (known as Fuel Rating Rule) sets out a uniform method by which the octane rating of automotive gasoline can be certified from the refiner through the chain of distribution and then displayed at the point of retail sale. The rule enables consumers to buy gasoline with an octane rating that is high enough to prevent inefficient and harmful "engine knock" and to avoid buying a gasoline with an octane rating that is needlessly higher than the requirements of their automobiles. The rule also establishes standard procedures for determining, certifying, and posting (by means of a label on the fuel dispenser) the rating of automotive fuels intended for sale to consumers. The certification requirement may be satisfied by industry documents (shipping receipts, delivery tickets, etc.) on which the rating is noted, or can be accomplished with a one-time letter of certification. In addition, the rule contains recordkeeping requirements that require refiners and importers to retain rating test records and distributors and retailers to retain certification records for 1 year.

On March 27, 2014, the Commission announced proposed ethanol labeling amendments to revise rating, certification and labeling requirements for blends of gasoline with more than 10 percent ethanol, and a new octane rating method that would lower compliance costs. The comment period closed on July 2, 2014. Staff is reviewing comments and anticipates sending a recommendation to the Commission by the end of the first quarter of 2015.