Tuesday, February 2, 2021 Treasury”) and the Internal Revenue Service (“ IRS”) published in the Final Regulations”) interpreting the excise tax under Section 4960 of the Internal Revenue Code on certain executive compensation paid by tax-exempt organizations. The Final Regulations maintain most of the concepts from the interim guidance (Notice 2019-09 (the “ Proposed Regulations”), discussed here), with a few changes. The Final Regulations became effective January 15, 2021, but they will apply only for tax years that start after December 31, 2021. Until then: Taxpayers may rely on the interim guidance under Notice 2019-09 or the Proposed Regulations, or the Final Regulations, but only if they apply the rules in their entirety; and