Final regulations on Source of Income from Certain Sales of Personal Property (TD 9921) from the U.S. IRS and Treasury were published in the Federal Register on 11 December 2020. As previously reported, the regulations concern changes made by the Tax Cuts and Jobs Act (TCJA) regarding sources of income and include: Modified rules for determining the source of income from sales of inventory produced within the U.S. and sold without the U.S. or vice versa; New rules for determining the source of income from sales of personal property (including inventory) by non-residents that are attributable to an office or...