ADTRAN Holdings, Inc. (ADTN)
Nasdaq: ADTN · Telephone & Telegraph Apparatus · Huntsville, AL · filing with the SEC since 1996
Grade4.8
◀ Past 3.4● Present 5.0▶ Future 6.0
Filings
410 filings since 2017 beside 651 insider forms · Large accelerated filer · read from EDGAR on Nov 13, 2026Due nextLarge accelerated filer
10-K
Annual report for the fiscal year ending Dec 31, 2026Large accelerated filers have 60 days after the fiscal year ends.
by Mar 1, 2027
10-Q
Quarterly report for the quarter ending Mar 31, 2027Large accelerated filers have 40 days after the quarter ends; quarter ends are taken to the month end.
by May 10, 2027
A deadline is the latest date the SEC's rules allow for its filer category. It is not a forecast of the day the company files. Last time, the results release (8-K item 2.02) came 34 days after the quarter ended. The proxy statement was last filed Mar 27, 2026.
Filings a yearinsider forms included
109101159209101676263
2026 counts to Nov 13, 2026.
Officer or director change (8-K item 5.02): 11 times in the last 36 months, the newest Oct 29, 2026.Warning not to rely on past financial statements (8-K item 4.02): 2 times in the last 36 months, the newest May 13, 2025.SEC letters: 5 in the last 36 months, the newest Nov 22, 2024.A late-filing notice, Form NT 10-Q, filed May 13, 2025.A late-filing notice, Form NT 10-K, filed Feb 29, 2024.
Insider forms (3, 4, 5 and 144) are counted each year but not listed here; the people and their trades are on the Ownership tab.
FiledFormWhat it is, in plain wordsPeriodAsk
Nov 3, 2026
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
Nov 2, 2026
Oct 29, 2026
8-K items 5.02, 8.01, 9.01
Officer or director change; Other event · Current report
Oct 27, 2026
Aug 4, 2026
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
Aug 3, 2026
Jul 23, 2026
8-K items 1.01, 1.02, 2.03, 9.01
Major agreement signed; Major agreement ended; New debt or obligation taken on · Current report
Jul 21, 2026
Jul 22, 2026
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
Jul 21, 2026
Jun 26, 2026
8-K items 5.02, 8.01, 9.01
Officer or director change; Other event · Current report
Jun 23, 2026
May 18, 2026
8-K items 5.03, 5.07, 9.01
Charter, bylaw or fiscal-year change; Shareholder vote · Current report
May 13, 2026
May 5, 2026
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
May 4, 2026
Feb 26, 2026
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
Feb 25, 2026
Jan 22, 2026
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
Jan 21, 2026
Nov 4, 2025
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
Nov 3, 2025
Sep 22, 2025
8-K items 1.01, 2.03, 3.02, 9.01
Major agreement signed; New debt or obligation taken on; Shares sold without registration · Current report
Sep 19, 2025
Sep 17, 2025
8-K items 1.01, 8.01, 9.01
Major agreement signed; Other event · Current report
Sep 15, 2025
Aug 5, 2025
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
Aug 4, 2025
Jul 17, 2025
8-K/A items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report, amended
Jul 16, 2025
Jul 16, 2025
8-K items 2.02, 7.01, 9.01
Results released; Investor disclosure (Regulation FD) · Current report
40 of 410 shown
Every row opens the filing on EDGAR. The plain words are the site's own for each form and each 8-K item; the complete history, insider forms included, is on EDGAR.