UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.     )

Filed by the Registrant  x
Filed by a Party other than the Registrant  o
Check the appropriate box:
o	Preliminary Proxy Statement
o	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
o	Definitive Proxy Statement
x	Definitive Additional Materials
o	Soliciting Material under §240.14a-12
United Therapeutics Corporation
(Name of Registrant as Specified In Its Charter)
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
Payment of Filing Fee (Check the appropriate box):
x	No fee required.
o	Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.
	(1)		Title of each class of securities to which transaction applies:
	(2)		Aggregate number of securities to which transaction applies:
	(3)		Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):
	(4)		Proposed maximum aggregate value of transaction:
	(5)		Total fee paid:
o	Fee paid previously with preliminary materials.
o	Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
	(1)	Amount Previously Paid:
	(2)	Form, Schedule or Registration Statement No.:
	(3)	Filing Party:
	(4)	Date Filed:

*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to Be Held on June 26, 2020. UNITED THERAPEUTICS CORPORATION UNITED THERAPEUTICS CORPORATION 1735 CONNECTICUT AVENUE, NW WASHINGTON, DC 20009 You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet or by mail. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. proxy materials and voting instructions. D13868-P39922 See the reverse side of this notice to obtain Meeting Information Meeting Type: Annual Meeting For holders as of: April 30, 2020 Date: June 26, 2020 Time: 10:15 AM EDT Location: Meeting live via the Internet-please visit www.virtualshareholdermeeting.com/UTHR2020. The company will be hosting the meeting live via the Internet this year. To attend the meeting via the Internet, please visit www.virtualshareholdermeeting.com/UTHR2020 and be sure to have the information that is printed in the box marked by the arrow (located on the following page). XXXX XXXX XXXX XXXX

Before You Vote How to Access the Proxy Materials How To Vote Please Choose One of the Following Voting Methods D13869-P39922 Vote By Internet: Before The Meeting: Go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow (located on the following page) available and follow the instructions. During The Meeting: Go to www.virtualshareholdermeeting.com/UTHR2020. Have the information that is printed in the box marked by the arrow(located on the following page) available and follow the instructions. Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card. XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX Proxy Materials Available to VIEW or RECEIVE: PROXY STATEMENTANNUAL REPORT ON FORM 10-K How to View Online: Have the information that is printed in the box marked by the arrow(located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one for this and future meetings. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET:www.proxyvote.com 2) BY TELEPHONE:1-800-579-1639 3) BY E-MAIL*:sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow(located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before June 12, 2020 to facilitate timely delivery. XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX

The Board of Directors recommends you vote FOR each of the following nominees: 1. Election of Directors 5. Ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for 2020 Nominees: 1a. Raymond Dwek NOTE: Such other business as may properly come before the meeting or any adjournment thereof. 1b. Christopher Patusky 1c. Tommy Thompson The Board of Directors recommends you vote FOR proposals 2, 3, 4 and 5. 2. Approval of an amendment to our Amended and Restated Certificate of Incorporation to declassify our Board of Directors and provide for the annual election of our directors 3. Advisory resolution to approve executive compensation 4. Approval of the amendment and restatement of the United Therapeutics Corporation Amended and Restated 2015 Stock Incentive Plan D13870-P39922 Voting Items

D13871-P39922