ADTRAN Holdings, Inc. SEC filings ADTN
ADTRAN Holdings, Inc. has 1,006 filings in SEC EDGAR's recent list, going back to Aug 21, 2017. Its latest annual report, Form ARS, was filed on Mar 27, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Nov 5, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Nov 3, 2026 (results of operations, regulation fd disclosure). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| 4 | Insider transaction | Nov 5, 2026 | Nov 3, 2026 |
| 10-Q | Quarterly report | Nov 5, 2026 | Sep 30, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 3, 2026 | Nov 2, 2026 |
| 4 | Insider transaction | Nov 2, 2026 | Oct 27, 2026 |
| 3 | Initial insider ownership | Nov 2, 2026 | Oct 27, 2026 |
| SCHEDULE 13G | Ownership over 5% (passive) | Oct 30, 2026 | — |
| 8-K |
Current report
Officer or director change, Other events
|
Oct 29, 2026 | Oct 27, 2026 |
| 8-K |
Current report
Officer or director change
|
Aug 10, 2026 | Aug 10, 2026 |
| 4 | Insider transaction | Aug 10, 2026 | Aug 10, 2026 |
| 4 | Insider transaction | Aug 7, 2026 | Aug 6, 2026 |
| 10-Q | Quarterly report | Aug 4, 2026 | Jun 30, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 4, 2026 | Aug 3, 2026 |
| 4 | Insider transaction | Jul 28, 2026 | Jul 24, 2026 |
| 8-K |
Current report
Material agreement, Agreement ended, New debt
|
Jul 23, 2026 | Jul 21, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Jul 22, 2026 | Jul 21, 2026 |
| S-3ASR | Automatic shelf registration | Jul 17, 2026 | — |
| 4 | Insider transaction | Jul 6, 2026 | Jul 1, 2026 |
| 3 | Initial insider ownership | Jul 1, 2026 | Jul 1, 2026 |
| 11-K | Employee savings plan report | Jun 26, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Officer or director change, Other events
|
Jun 26, 2026 | Jun 23, 2026 |
| 4 | Insider transaction | May 22, 2026 | May 20, 2026 |
| 144 | Notice of proposed sale | May 20, 2026 | — |
| 8-K |
Current report
Bylaw or fiscal year change, Shareholder vote results
|
May 18, 2026 | May 13, 2026 |
| SD | Specialized disclosure (conflict minerals) | May 12, 2026 | — |
| 4 | Insider transaction | May 11, 2026 | May 7, 2026 |
| 144 | Notice of proposed sale | May 7, 2026 | — |
| 10-Q | Quarterly report | May 5, 2026 | Mar 31, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 5, 2026 | May 4, 2026 |
| DEFA14A | Additional proxy material | May 1, 2026 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Apr 28, 2026 | — |
| 8-K |
Current report
Officer or director change
|
Apr 7, 2026 | Apr 1, 2026 |
| 4 | Insider transaction | Apr 3, 2026 | Apr 1, 2026 |
| 4 | Insider transaction | Apr 3, 2026 | Apr 1, 2026 |
| 4 | Insider transaction | Apr 3, 2026 | Apr 1, 2026 |
| ARS | Annual report to shareholders | Mar 27, 2026 | Dec 31, 2025 |
| DEFA14A | Additional proxy material | Mar 27, 2026 | — |
| DEF 14A | Proxy statement | Mar 27, 2026 | Mar 27, 2026 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Mar 26, 2026 | — |
| 4 | Insider transaction | Mar 23, 2026 | Mar 19, 2026 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Mar 18, 2026 | — |
| PRE 14A | Preliminary proxy statement | Mar 13, 2026 | Mar 13, 2026 |
| 4 | Insider transaction | Mar 5, 2026 | Mar 4, 2026 |
| 4/A | Filing | Mar 5, 2026 | Jan 24, 2025 |
| 144 | Notice of proposed sale | Mar 4, 2026 | — |
| 10-K | Annual report | Feb 26, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 26, 2026 | Feb 25, 2026 |
| 4/A | Filing | Jan 30, 2026 | Jan 26, 2026 |
| 4 | Insider transaction | Jan 28, 2026 | Jan 26, 2026 |
| 4 | Insider transaction | Jan 28, 2026 | Jan 26, 2026 |
| 4 | Insider transaction | Jan 27, 2026 | Jan 24, 2026 |
| 4 | Insider transaction | Jan 27, 2026 | Jan 24, 2026 |
| 4 | Insider transaction | Jan 22, 2026 | Jan 20, 2026 |
| 4 | Insider transaction | Jan 22, 2026 | Jan 20, 2026 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Jan 22, 2026 | Jan 21, 2026 |
| 4 | Insider transaction | Jan 5, 2026 | Dec 31, 2025 |
| 4 | Insider transaction | Jan 5, 2026 | Dec 31, 2025 |
| 4 | Insider transaction | Jan 5, 2026 | Dec 31, 2025 |
| 4 | Insider transaction | Jan 5, 2026 | Dec 31, 2025 |
| 4 | Insider transaction | Jan 5, 2026 | Dec 31, 2025 |
| 4 | Insider transaction | Jan 5, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Officer or director change
|
Dec 11, 2025 | Dec 9, 2025 |
| 4 | Insider transaction | Dec 1, 2025 | Nov 28, 2025 |
| 4 | Insider transaction | Dec 1, 2025 | Nov 26, 2025 |
| 4 | Insider transaction | Nov 25, 2025 | Nov 24, 2025 |
| 4 | Insider transaction | Nov 19, 2025 | Nov 17, 2025 |
| 4 | Insider transaction | Nov 19, 2025 | Nov 17, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Nov 14, 2025 | — |
| 10-Q | Quarterly report | Nov 4, 2025 | Sep 30, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 4, 2025 | Nov 3, 2025 |
| 8-K |
Current report
Material agreement, New debt, Unregistered share sale
|
Sep 22, 2025 | Sep 19, 2025 |
| 8-K |
Current report
Material agreement, Other events
|
Sep 17, 2025 | Sep 15, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Aug 14, 2025 | — |
| 10-Q | Quarterly report | Aug 5, 2025 | Jun 30, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 5, 2025 | Aug 4, 2025 |
| 8-K |
Current report
Shareholder vote results, Other events
|
Jul 30, 2025 | Jul 24, 2025 |
| 8-K/A |
Amended current report
Results of operations, Regulation FD disclosure
|
Jul 17, 2025 | Jul 16, 2025 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Jul 16, 2025 | Jul 16, 2025 |
| 4 | Insider transaction | Jul 15, 2025 | Jul 13, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Jul 7, 2025 | — |
| 11-K | Employee savings plan report | Jun 30, 2025 | Dec 31, 2024 |
| ARS/A | Filing | Jun 6, 2025 | Dec 31, 2024 |
| DEFA14A | Additional proxy material | Jun 6, 2025 | — |
| DEFR14A | Filing | Jun 6, 2025 | — |
| SD | Specialized disclosure (conflict minerals) | May 29, 2025 | — |
| 8-K |
Current report
Results of operations
|
May 28, 2025 | May 27, 2025 |
| DEFA14A | Additional proxy material | May 27, 2025 | — |
| 8-K |
Current report
Other events
|
May 27, 2025 | May 27, 2025 |
| 10-Q | Quarterly report | May 20, 2025 | Mar 31, 2025 |
| 10-K/A | Amended annual report | May 20, 2025 | Dec 31, 2024 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | May 15, 2025 | — |
| DEFA14A | Additional proxy material | May 13, 2025 | — |
| NT 10-Q | Filing | May 13, 2025 | May 13, 2025 |
| 8-K |
Current report
Restatement, Other events
|
May 13, 2025 | May 13, 2025 |
| 8-K |
Current report
Material agreement
|
May 12, 2025 | May 6, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | May 9, 2025 | — |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 8, 2025 | May 7, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Apr 23, 2025 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Apr 16, 2025 | Apr 15, 2025 |
| 4 | Insider transaction | Apr 15, 2025 | Apr 13, 2025 |
| ARS | Annual report to shareholders | Mar 31, 2025 | Dec 31, 2024 |
| DEFA14A | Additional proxy material | Mar 31, 2025 | — |
| DEF 14A | Proxy statement | Mar 31, 2025 | Mar 31, 2025 |
| 4 | Insider transaction | Mar 20, 2025 | Mar 19, 2025 |
| 3 | Initial insider ownership | Mar 20, 2025 | Mar 10, 2025 |
| 8-K |
Current report
Officer or director change, Regulation FD disclosure
|
Mar 7, 2025 | Mar 6, 2025 |
| SCHEDULE 13G | Ownership over 5% (passive) | Mar 6, 2025 | — |
| 10-K | Annual report | Mar 3, 2025 | Dec 31, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 27, 2025 | Feb 26, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Feb 14, 2025 | — |
| 4 | Insider transaction | Jan 28, 2025 | Jan 24, 2025 |
| 4 | Insider transaction | Jan 28, 2025 | Jan 24, 2025 |
| 4 | Insider transaction | Jan 28, 2025 | Jan 24, 2025 |
| 4 | Insider transaction | Jan 28, 2025 | Jan 24, 2025 |
| 4 | Insider transaction | Jan 22, 2025 | Jan 20, 2025 |
| 4 | Insider transaction | Jan 22, 2025 | Jan 20, 2025 |
| 4 | Insider transaction | Jan 15, 2025 | Jan 13, 2025 |
| 4 | Insider transaction | Jan 3, 2025 | Dec 31, 2024 |
| 4 | Insider transaction | Jan 3, 2025 | Dec 31, 2024 |
| 4 | Insider transaction | Jan 3, 2025 | Dec 31, 2024 |
| 4 | Insider transaction | Jan 3, 2025 | Dec 31, 2024 |
| 4 | Insider transaction | Jan 3, 2025 | Dec 31, 2024 |
| 4 | Insider transaction | Jan 3, 2025 | Dec 31, 2024 |
| EFFECT | Filing | Nov 26, 2024 | — |
| CORRESP | Letter to the SEC | Nov 22, 2024 | — |
| UPLOAD | Letter from the SEC | Nov 21, 2024 | — |
| 4 | Insider transaction | Nov 19, 2024 | Nov 16, 2024 |
| 4 | Insider transaction | Nov 19, 2024 | Nov 16, 2024 |
| S-3 | Shelf registration | Nov 18, 2024 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Nov 14, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Nov 14, 2024 | — |
| 10-Q | Quarterly report | Nov 12, 2024 | Sep 30, 2024 |
| SC 13G/A | Amended ownership over 5% (passive) | Nov 12, 2024 | — |
| SC 13G | Ownership over 5% (passive) | Nov 12, 2024 | — |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 7, 2024 | Nov 6, 2024 |
| UPLOAD | Letter from the SEC | Nov 4, 2024 | — |
| SC 13G | Ownership over 5% (passive) | Nov 4, 2024 | — |
| 4 | Insider transaction | Oct 15, 2024 | Oct 13, 2024 |
| CORRESP | Letter to the SEC | Sep 27, 2024 | — |
| UPLOAD | Letter from the SEC | Sep 26, 2024 | — |
| 8-K |
Current report
Officer or director change
|
Aug 30, 2024 | Aug 27, 2024 |
| 10-Q | Quarterly report | Aug 9, 2024 | Jun 30, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 6, 2024 | Aug 5, 2024 |
| 8-K |
Current report
Officer or director change
|
Aug 2, 2024 | Jul 31, 2024 |
| 4/A | Filing | Jul 17, 2024 | Jul 13, 2024 |
| 4 | Insider transaction | Jul 16, 2024 | Jul 13, 2024 |
| SC 13G/A | Amended ownership over 5% (passive) | Jul 8, 2024 | — |
| 11-K | Employee savings plan report | Jun 28, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Material agreement, New debt
|
Jun 10, 2024 | Jun 4, 2024 |
| 4 | Insider transaction | May 29, 2024 | May 24, 2024 |
| 4 | Insider transaction | May 29, 2024 | May 24, 2024 |
| SD | Specialized disclosure (conflict minerals) | May 22, 2024 | — |
| S-8 | Employee stock plan registration | May 10, 2024 | — |
| S-8 | Employee stock plan registration | May 10, 2024 | — |
| 10-Q | Quarterly report | May 10, 2024 | Mar 31, 2024 |
| 8-K |
Current report
Officer or director change, Shareholder vote results
|
May 9, 2024 | May 8, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 7, 2024 | May 6, 2024 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 3, 2024 | May 3, 2024 |
| 8-K |
Current report
Exit or restructuring costs
|
Apr 17, 2024 | Apr 11, 2024 |
| DEFA14A | Additional proxy material | Apr 4, 2024 | — |
| ARS | Annual report to shareholders | Mar 27, 2024 | Dec 31, 2023 |
| DEFA14A | Additional proxy material | Mar 27, 2024 | — |
| DEF 14A | Proxy statement | Mar 27, 2024 | May 8, 2024 |
| SC 13G | Ownership over 5% (passive) | Mar 25, 2024 | — |
| 10-K | Annual report | Mar 15, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Results of operations
|
Mar 15, 2024 | Mar 15, 2024 |
| 10-Q/A | Amended quarterly report | Mar 15, 2024 | Sep 30, 2023 |
| 10-Q/A | Amended quarterly report | Mar 15, 2024 | Jun 30, 2023 |
| 10-Q/A | Amended quarterly report | Mar 15, 2024 | Mar 31, 2023 |
| NT 10-K | Filing | Feb 29, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Feb 27, 2024 | Feb 26, 2024 |
| 8-K |
Current report
Restatement
|
Feb 20, 2024 | Feb 20, 2024 |
| SC 13G | Ownership over 5% (passive) | Feb 12, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 12, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 12, 2024 | — |
| 4 | Insider transaction | Jan 30, 2024 | Jan 26, 2024 |
| 4 | Insider transaction | Jan 30, 2024 | Jan 26, 2024 |
| 4 | Insider transaction | Jan 30, 2024 | Jan 26, 2024 |
| 4 | Insider transaction | Jan 30, 2024 | Jan 26, 2024 |
| 4 | Insider transaction | Jan 23, 2024 | Jan 20, 2024 |
| 4 | Insider transaction | Jan 23, 2024 | Jan 20, 2024 |
| SC 13G/A | Amended ownership over 5% (passive) | Jan 22, 2024 | — |
| 8-K |
Current report
Material agreement, New debt
|
Jan 22, 2024 | Jan 16, 2024 |
| 4 | Insider transaction | Jan 3, 2024 | Dec 31, 2023 |
| 4 | Insider transaction | Jan 3, 2024 | Dec 31, 2023 |
| 4 | Insider transaction | Jan 3, 2024 | Dec 31, 2023 |
| 4 | Insider transaction | Jan 3, 2024 | Dec 31, 2023 |
| 4 | Insider transaction | Jan 3, 2024 | Dec 31, 2023 |
| 4 | Insider transaction | Jan 3, 2024 | Dec 31, 2023 |
| 4 | Insider transaction | Jan 3, 2024 | Dec 31, 2023 |
| 4 | Insider transaction | Dec 8, 2023 | Dec 7, 2023 |
| 8-K |
Current report
Officer or director change
|
Dec 6, 2023 | Dec 4, 2023 |
| 8-K |
Current report
Officer or director change
|
Dec 5, 2023 | Dec 1, 2023 |
| 4 | Insider transaction | Dec 4, 2023 | Dec 1, 2023 |
| 4 | Insider transaction | Nov 20, 2023 | Nov 16, 2023 |
| 4 | Insider transaction | Nov 20, 2023 | Nov 16, 2023 |
| 4 | Insider transaction | Nov 17, 2023 | Nov 15, 2023 |
| 4 | Insider transaction | Nov 17, 2023 | Nov 15, 2023 |
| 10-Q | Quarterly report | Nov 9, 2023 | Sep 30, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Nov 7, 2023 | Nov 6, 2023 |
| 8-K |
Current report
Officer or director change, Bylaw or fiscal year change
|
Oct 24, 2023 | Oct 18, 2023 |
Showing 200 filings, the most recent 200. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Telephone & Telegraph Apparatus (SIC 3661)
- Listed as
- ADTN (Nasdaq)
- Fiscal year ends
- December 31
- Headquarters
- Huntsville, AL
- SEC filer status
- Large accelerated filer
- SEC CIK
- 926282
- Former names
- ADTRAN INC (until Jul 11, 2022)
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Source: SEC EDGAR filings. This is company-reported data, not investment advice.