X0306 4/A 2016-06-21 2016-06-23 0001082554 UNITED THERAPEUTICS Corp UTHR 0001108501 KURZWEIL RAY C/O UNITED THERAPEUTICS CORPORATION 1040 SPRING STREET SILVER SPRING MD 20910 1 Stock Options 101.80 2016-06-21 4 A 0 4910 0 A 2017-06-21 2026-06-21 Common Stock 4910 4910 D The purpose of this amendment is to correct an overstatement of the number of shares subject to the stock option awarded to the reporting person on June 21, 2016, by 90 shares. The original Form 4 filing on June 23, 2016 reported 5,000 shares subject to this stock option. /s/ John S. Hess, Jr. under Power of Attorney 2017-03-07