In late 2019, the I.R.S. proposed regulations modifying rules for determining the source of income from sales of inventory property produced by a taxpayer outside the U.S. and sold within the U.S., or produced by the taxpayer within and sold without the U.S. Final regulations were published in October. The regulations implement changes made by the Tax Cuts and Jobs Act provide guidance under Code §865(e)(2) regarding sales of inventory through a U.S. office or fixed place of business. In her article, Léa Verdy, an attorney admitted to practice in New York and Paris, presents the sourcing rules for sales of inventory before the T.C.J.A, the changes implemented by the T.C.J.A., the guidance offered by the I.R.S., and the consequences of the regulations for taxpayers.