On October 8, 2019, the US Internal Revenue Service released proposed regulations addressing the US federal tax consequences of replacing an interbank offered rate (IBOR) with a successor rate. The proposed regulations generally provide the circumstances in which the replacement of an IBOR with a fallback rate, or an addition of a fallback mechanic to an existing instrument, will not result in a deemed exchange of the instrument under Section 1001 of the Internal Revenue Code of 1986, as amended. The proposed regulations also provide guidance on other considerations with respect to the transition away from IBORs. Mayer Brown partners Russell Nance and Steven Garden and associate Brennan Young provide an overview of the proposed regulations.