Adtran Holdings, Inc.

Adtran Holdings, Inc.: Release according to Article 40, Section 1 of the WpHG [the German Securities Trading Act] with the objective of Europe-wide distribution

29.06.2026 / 13:09 CET/CEST

Dissemination of a Voting Rights Announcement transmitted by - a service of .

The issuer is solely responsible for the content of this announcement.

Notification of Major Holdings1. Details of issuer
Name:Adtran Holdings, Inc.Street:901 Explorer BoulevardPostal code:35806City:HuntsvilleUnited StatesLegal Entity Identifier (LEI):549300VV36J86CRRWF77
2. Reason for notification
 Acquisition/disposal of shares with voting rightsXAcquisition/disposal of instruments Change of breakdown of voting rights Other reason:
3. Details of person subject to the notification obligation

Legal entity: The Goldman Sachs Group, Inc.City of registered office, country: Wilmington, DE, United States of America (USA)

4. Names of shareholder(s) holding directly 3% or more voting rights, if different from 3.5. Date on which threshold was crossed or reached:

23 Jun 2026

6. Total positions
 % of voting rights attached to shares (total of 7.a.)% of voting rights through instruments (total of 7.b.1 + 7.b.2)Total of both in % (7.a. + 7.b.)Total number of voting rights pursuant to Sec. 41 WpHGNew0.95 %4.01 %4.95 %81421186Previous notification0.97 %4.30 %5.27 %/
7. Details on total positions a. Voting rights attached to shares (Sec. 33, 34 WpHG)
ISINAbsoluteIn % Direct (Sec. 33 WpHG)Indirect (Sec. 34 WpHG)Direct (Sec. 33 WpHG)Indirect (Sec. 34 WpHG)US00486H105907712000 %0.95 %Total7712000.95 %
b.1. Instruments according to Sec. 38 (1) no. 1 WpHG
Type of instrumentExpiration or maturity dateExercise or conversion periodVoting rights absoluteVoting rights in %Right To RecallOpen4933600.61 %Right Of UseOpen25946823.19 %  Total30880423.79 %
b.2. Instruments according to Sec. 38 (1) no. 2 WpHG
Type of instrumentExpiration or maturity dateExercise or conversion periodCash or physical settlementVoting rights absoluteVoting rights in %Swap15.01.2030Cash1748390.21 %   Total1748390.21 %
8. Information in relation to the person subject to the notification obligation
 Person subject to the notification obligation is not controlled nor does it control any other undertaking(s) that directly or indirectly hold(s) an interest in the (underlying) issuer (1.).XFull chain of controlled undertakings starting with the ultimate controlling natural person or legal entity:
Name% of voting rights (if at least 3% or more)% of voting rights through instruments (if at least 5% or more)Total of both (if at least 5% or more)The Goldman Sachs Group, Inc. % % %GSAM Holdings LLC % % %Goldman Sachs Asset Management, L.P. % % %- % % %The Goldman Sachs Group, Inc. % % %Folio Financial, Inc. % % %Folio Investments, Inc. % % %- % % %The Goldman Sachs Group, Inc. % % %Goldman Sachs & Co. LLC % % %- % % %The Goldman Sachs Group, Inc. % % %Goldman Sachs (UK) L.L.C. % % %Goldman Sachs Group UK Limited % % %Goldman Sachs International % % %
9. In case of proxy voting according to Sec. 34 para. 3 WpHG (only in case of attribution of voting rights in accordance with Sec. 34 para. 1 sent. 1 No. 6 WpHG) Date of general meeting: Holding total positions after general meeting (6.) after annual general meeting:
Proportion of voting rights %Proportion of instruments %Total of both %
10. Other explanatory remarks: Date

26 Jun 2026

29.06.2026 CET/CEST The EQS Distribution Services include Regulatory Announcements, Financial/Corporate News and Press Releases.

Language:EnglishCompany:Adtran Holdings, Inc.901 Explorer Boulevard35806 HuntsvilleUnited StatesInternet:www.adtran.com
 End of NewsEQS News Service

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