Adtran Holdings, Inc.

ADTN·NASDAQ·$16.49Share Price as of 11/2·$1BMarket Cap as of 11/2

Financials

10-QQ2 ended 06/30/2608/04/26 10-QQ1 ended 03/31/2605/05/26 10-KFY 202502/26/26 10-QQ3 ended 09/30/2511/04/25 10-QQ2 ended 06/30/2508/05/25

Disclosures

8-KCurrent report10/29/26 8-KCurrent report08/10/26 8-KCurrent report08/04/26 8-KCurrent report07/23/26 8-KCurrent report07/22/26

Prospectuses and Registrations

S-3ASRAutomatic shelf registration07/17/26 S-3Shelf registration11/18/24 S-8Registration of securities for employees05/10/24 S-8Registration of securities for employees05/10/24 S-3ASRAutomatic shelf registration12/23/22

Proxies

DEFA14AAdditional proxy materials05/01/26 DEF 14ADefinitive proxy03/27/26 DEFA14AAdditional proxy materials03/27/26 PRE 14APreliminary proxy03/13/26 DEFA14AAdditional proxy materials06/06/25

Ownership

Form 4Insider transaction08/10/26 Form 4Insider transaction08/07/26 Form 4Insider transaction07/28/26 Form 4Insider transaction07/06/26 Form 3Initial insider ownership07/01/26

Other

11-KEmployee stock purchase plan report06/26/26 SDConflict Minerals disclosure05/12/26 ARSAnnual report to shareholders03/27/26 11-KEmployee stock purchase plan report06/30/25 ARS/AARS/A06/06/25