The U.S. IRS has formally announced two competent authority arrangements with the UK in Internal Revenue Bulletin: 2021-33, issued 16 August 2021. As previously reported, the arrangements concern the application of the "derivative benefits test" in paragraph 3 of Article 23 (Limitation on benefits) of the 2001 US-UK Tax Treaty and the interpretation of the term "North American Free Trade Agreement" considering the signing of the United States-Mexico-Canada Agreement (USMCA). --- TAX CONVENTIONS Announcement 2021-13, page 314. The competent authorities of the United States and the United Kingdom have entered into a Competent Authority Arrangement under paragraph 3 of Article...