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EXCEL - IDEA: XBRL DOCUMENT - UNITED THERAPEUTICS CorpFinancial_Report.xls
EX-23.1 - EX-23.1 - UNITED THERAPEUTICS Corpa2223076zex-23_1.htm
EX-32.1 - EX-32.1 - UNITED THERAPEUTICS Corpa2223076zex-32_1.htm
EX-32.2 - EX-32.2 - UNITED THERAPEUTICS Corpa2223076zex-32_2.htm
EX-31.2 - EX-31.2 - UNITED THERAPEUTICS Corpa2223076zex-31_2.htm
EX-31.1 - EX-31.1 - UNITED THERAPEUTICS Corpa2223076zex-31_1.htm
EX-10.55 - EX-10.55 - UNITED THERAPEUTICS Corpa2223076zex-10_55.htm
EX-10.54 - EX-10.54 - UNITED THERAPEUTICS Corpa2223076zex-10_54.htm
EX-10.56 - EX-10.56 - UNITED THERAPEUTICS Corpa2223076zex-10_56.htm
10-K - 10-K - UNITED THERAPEUTICS Corpa2223076z10-k.htm

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Exhibit 21

SUBSIDIARIES OF THE REGISTRANT

EvoLung Inc., a Delaware Corporation
Lung Bioengineering Inc., a Delaware Corporation
Lung Biotechnology Hong Kong Limited, a Hong Kong Company
Lung Biotechnology Inc., a Delaware Corporation
Lung Biotechnology (Nanjing) Co., Ltd., a Chinese Wholly Foreign-Owned Entity
Lung Rx Limited, a United Kingdom Company
PERFUSIX USA, Inc., a Delaware Corporation
Revivicor, Inc., a Delaware Corporation
United Therapeutics Europe, Ltd., a United Kingdom Company
Unither Biotech Inc., a Canadian Corporation
Unither Pharma, LLC, a Delaware Limited Liability Company
Unither Pharmaceuticals, LLC, a Delaware Limited Liability Company
Unither Telmed, Ltd., a Delaware Corporation
Unither Therapeutik GmbH, a German Company
Unither Virology, LLC, a Delaware Limited Liability Company
Unither.com, Inc., a Delaware Corporation
UTASIA Inc., a Delaware Corporation
1109 Spring Managing Holdings, LLC, a Delaware Limited Liability Company
1109 Spring Managing Member, LLC, a Delaware Limited Liability Company




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SUBSIDIARIES OF THE REGISTRANT