X0306 4/A 2018-03-15 2021-03-16 0001082554 UNITED THERAPEUTICS Corp UTHR 0001106578 ROTHBLATT MARTINE A C/O UNITED THERAPEUTICS CORPORATION 1040 SPRING STREET SILVER SPRING MD 20910 1 1 Chairman & CEO Common Stock 140 D Common Stock 166 I By Spouse Common Stock 662366 I By Trusts Stock Options 111.00 2018-03-15 4 A 0 285103 0 A 2021-03-15 2028-03-15 Common Stock 285103 285103 D Stock Options 113.08 2013-12-31 2023-12-31 Common Stock 1000000 1000000 D Stock Options 129.49 2014-12-31 2024-12-31 Common Stock 723869 723869 D Stock Options 120.26 2017-03-15 2026-03-15 Common Stock 294000 294000 D These performance-based stock options were initially awarded on March 15, 2018, subject to a three-year performance condition tied to average cash profit margin during 2018-2020, which was determined on February 24, 2021. Number of stock options reported represents the number of options earned based on performance. This Form 4/A is being filed to correct the expiration date of this award. This stock option was transferred from a trust beneficially owned by the reporting person on March 1, 2021. /s/ John S. Hess, Jr. under Power of Attorney 2021-03-16