The amending protocol to the 1996 income and capital tax treaty between Luxembourg and the U.S. entered into force on 9 September 2019. The protocol, signed 20 May 2009, replaces Article 28 (Exchange of Information). The protocol is the first to amend the treaty and applies for information requests made on or after the date of entry into force with regard to tax years beginning on or after 1 January 2009.