Doug McHoney (PwC's US International Tax Services (ITS) Leader) and Rebecca Lee (ITS Partner in Washington National Tax Services) discuss the recently-issued Section 163(j) final and proposed regulations. Doug and Rebecca discuss: what Section 163(j) is and how the Tax Cuts and Jobs Act changed the interest expense limitation rules for corporations; effective dates for both the final and proposed regulations; how the final regulations define 'interest;' the breadth of the anti-avoidance rule in the final regulations; how the final regulations define 'adjusted taxable income' and 'tentative taxable income;' how the final regulations treat the separate return limitation year (SRLY) limitation; and major takeaways of the proposed regulations, including how the proposed regulations treat controlled foreign corporations (CFCs), foreign persons with effectively-connected income (ECI), and partnerships.