ARGX argenx SE

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the Month of March 2020

Commission File Number: 001-38097

ARGENX SE

(Translation of registrant’s name into English)

Willemstraat 5
4811 AH, Breda, the Netherlands

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  x     Form 40-F  o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): o

EXPLANATORY NOTE

Enclosed hereto as Exhibits 99.1, 99.2, 99.3, 99.4, 99.5, 99.6 and 99.7 and incorporated herein by reference are copies of the formal notice of convocation, agenda, and other ancillary documents relevant for argenx SE’s (the “Company’s) Annual General Meeting of Shareholders that will be held on Tuesday, May 12, 2020 at 9:00 a.m. (CET), at Hilton Amsterdam Airport Schiphol, Schiphol Boulevard 701, 1118 BG Schiphol, the Netherlands.

The information contained in this Current Report on Form 6-K, including the exhibits hereto, is incorporated by reference into the Company’s Registration Statements on Forms F-3 (File No. 333-225370) and S-8 (File No. 333-225375).

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