StacksVerified U.S. regulatory reference

49 CFR §534.4

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
For purposes of the fuel economy and fuel consumption programs, “manufacturer” includes “predecessors” and “successors” to the extent specified in this section.
  1. (a)Successors are responsible for any civil penalties that arise out of fuel economy and fuel consumption shortfalls incurred and not satisfied by predecessors.
  2. (b)If one manufacturer has become the successor of another manufacturer during a model year, all of the vehicles or engines produced by those manufacturers during the model year are treated as though they were manufactured by the same manufacturer. A manufacturer is considered to have become the successor of another manufacturer during a model year if it is the successor on September 30 of the corresponding calendar year and was not the successor for the preceding model year.
  3. (c)
    1. (1)For passenger automobiles and light trucks, fuel economy credits earned by a predecessor before or during model year 2007 may be used by a successor, subject to the availability of credits and the general three-year restriction on carrying credits forward and the general three-year restriction on carrying credits backward. Fuel economy credits earned by a predecessor after model year 2007 may be used by a successor, subject to the availability of credits and the general five-year restriction on carrying credits forward and the general three-year restriction on carrying credits backward.
    2. (2)For heavy-duty vehicles and heavy-duty vehicle engines, available fuel consumption credits earned by a predecessor after model year 2015, and in model years 2013, 2014 and 2015 if a manufacturer voluntarily complies in those model years, may be used by a successor, subject to the availability of credits and the general five-year restriction on carrying credits forward and the general three year restriction on carrying credits backward.
  4. (d)
    1. (1)For passenger automobiles and light trucks, fuel economy credits earned by a successor before or during model year 2007 may be used to offset a predecessor's shortfall, subject to the availability of credits and the general three-year restriction on carrying credits forward and the general three-year restriction on carrying credits backward. Credits earned by a successor after model year 2007 may be used to offset a predecessor's shortfall, subject to the availability of credits and the general five-year restriction on carrying credits forward and the general three-year restriction on carrying credits backward.
    2. (2)For heavy-duty vehicles and heavy-duty vehicle engines, available credits earned by a successor after model year 2015, and in model years 2013, 2014 and 2015, if a manufacturer voluntarily complies in those model years, may be used by a predecessor subject to the availability of credits and the general five-year restriction on carrying credits forward and the general three year restriction on carrying credits backward.