On March 28, 2017, the US Tax Court (Tax Court) issued its opinion in Good Fortune Shipping SA v. Commissioner, 148 T.C. No. 10, upholding the validity of Treas. Reg. § 1.883-4. The taxpayer had challenged the validity of the regulation’s provision that stock in the form of “bearer shares” cannot be counted for purposes of determining the more-than-50-percent ownership test under Internal Revenue Code (Code) section 883(c)(1), but the Tax Court held that the regulation was valid under the two-step analysis of Chevron USA, Inc. v. Natural Resources Defense Council, 467 U.S. 837 (1984), and applied it in ruling for the Internal Revenue Service (IRS). We previously discussed the Tax Court’s opinion here. The taxpayer appealed the Tax Court’s decision to the US Court of Appeals for the District of Columbia Circuit (DC Circuit).