From the Overview: "On December 10, 2019, the United States, Canada, and Mexico agreed to a protocol of amendment to the proposed U.S.-Mexico-Canada Agreement (USMCA). The amendments include modifications to key elements of the original text in regard to dispute settlement, labor and environmental provisions, intellectual property rights (IPR), and steel and aluminum requirements in the rules of origin for autos. On December 13, the Trump Administration submitted to Congress the proposed USMCA implementing legislation, which also reflects the recent amendments. On the same day, the United States-Mexico-Canada Implementation Act (H.R. 5430) was introduced in the House of Representatives. On December 16, the companion bill was introduced in the Senate (S. 3052). The House Ways and Means Committee approved the legislation on December 17, 2019, and the full House approved it on December 19, 2019, by a vote of 385-41. On January 7, 2020, the Senate Finance Committee approved the legislation."
CRS In Focus, IF11391
Congressional Research Service: https://crsreports.congress.gov/