avtr-20251217

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 17, 2025

Avantor, Inc.

(Exact name of registrant as specified in its charter)


Delaware	001-38912	82-2758923
(State or other jurisdiction of incorporation)	(Commission File Number)	(I.R.S. Employer Identification No.)

Radnor Corporate Center, Building One, Suite 200

100 Matsonford Road

Radnor, Pennsylvania 19087

(Address of principal executive offices, including zip code)

(610) 386-1700

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, $0.01 par value

AVTR

New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). ☐ Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On December 17, 2025, Avantor, Inc. (the “Company”) filed a Current Report on Form 8-K announcing the election of Simon Dingemans as a director of the Company effective January 2, 2026. The prior report did not include the committees of the Board of Directors that Mr. Dingemans was named to because the Board had not determined on which committees of the Board Mr. Dingemans would serve. This Form 8-K/A is being filed for the purpose of providing this information.

Effective February 19, 2026, Mr. Dingemans was appointed to serve on the Audit & Finance Committee.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits


Exhibit No.						Description
104						The cover page from this Current Report on Form 8-K/A, formatted in Inline XBRL

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 hereunto duly authorized.


	Avantor, Inc.

Date: February 25, 2026	By:	/s/ Claudius Sokenu
		Name:	Claudius Sokenu
		Title:	Executive Vice President, Chief Legal and Compliance Officer and Secretary (Duly Authorized Officer)

Amendment: Avantor Inc. filed SEC Form 8-K: Leadership Update, Financial Statements and Exhibits