Report of Foreign Issuer (6-k)

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: November 2018

Commission File Number: 001-36563

Orion Engineered Carbons S.A.

(Translation of registrant’s name into English)

6, Route de Trèves

L-2633 Senningerberg (Municipality of Niederanven)

Grand Duchy of Luxembourg

(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

On November 5th, 2018, Mr. Corning F. Painter, Chief Executive Officer of Orion Engineered Carbons S.A. (the “Company”), purchased a total of 36,950 common shares of the Company. The shares were purchased at an average price of $ 27.30 per share. Mr. Painter took this opportunity to buy the Company’s stock upon the opening of the first window period following his appointment as CEO and director of the Company and in compliance with the Company’s policies.

Except as required by law, the Company generally does not commit to announce further acquisitions or dispositions of its common shares by its officers or directors.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.