The North American and global automotive sector is watching closely to see how the United States ultimately responds to the decision of December 14, 2022, made public on January 10, 2023, which upheld Canada’s and Mexico’s position on an important issue for calculation of a vehicle’s regional value content (RVC) under the USMCA. In dispute was whether a Core Part or Super Core Part that qualifies as originating under Articles 3.7 to 3.9 of the USMCA Auto Appendix can then have 100% of its value count as originating content when calculating the RVC of the fully assembled vehicle. The United States had argued that there was a separate “origination requirement” for Core Parts and Super Core Parts which, once satisfied, had no input into the vehicle RVC calculation. Instead, the United States argued, the vehicle RVC calculation would need to proceed from scratch, without the “roll-up” represented by the 100% value of originating Core Parts and Super Core Parts entering the vehicle RVC calculation. One consequence of the U.S. approach would have been on producers’ use of Chapter 4, Article 4.8, which limits them to just one layer of intermediate material roll-up on self-produced intermediate materials.