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 |
|---|---|---|---|
| 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 |
| 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 |
| 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 |
| 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 | — |
| 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 |
| 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 | — |
| 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 | — |
| 8-K |
Current report
Officer or director change
|
Apr 7, 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 |
| PRE 14A | Preliminary proxy statement | Mar 13, 2026 | Mar 13, 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 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Jan 22, 2026 | Jan 21, 2026 |
| 8-K |
Current report
Officer or director change
|
Dec 11, 2025 | Dec 9, 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 |
| 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 |
| 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 |
| 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 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
May 8, 2025 | May 7, 2025 |
| 8-K |
Current report
Regulation FD disclosure
|
Apr 16, 2025 | Apr 15, 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 |
| 8-K |
Current report
Officer or director change, Regulation FD disclosure
|
Mar 7, 2025 | 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 |
| EFFECT | Filing | Nov 26, 2024 | — |
| CORRESP | Letter to the SEC | Nov 22, 2024 | — |
| UPLOAD | Letter from the SEC | Nov 21, 2024 | — |
| S-3 | Shelf registration | Nov 18, 2024 | — |
| 10-Q | Quarterly report | Nov 12, 2024 | Sep 30, 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 | — |
| 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 |
| 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 |
| 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 |
| 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 |
| 8-K |
Current report
Material agreement, New debt
|
Jan 22, 2024 | Jan 16, 2024 |
| 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 |
| 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 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Oct 17, 2023 | Oct 16, 2023 |
| 8-K |
Current report
Officer or director change
|
Sep 29, 2023 | Sep 25, 2023 |
| 8-K/A |
Amended current report
Results of operations
|
Aug 14, 2023 | Aug 6, 2023 |
| 10-Q | Quarterly report | Aug 14, 2023 | Jun 30, 2023 |
| 10-Q/A | Amended quarterly report | Aug 14, 2023 | Mar 31, 2023 |
| 10-K/A | Amended annual report | Aug 14, 2023 | Dec 31, 2022 |
| 10-Q/A | Amended quarterly report | Aug 14, 2023 | Sep 30, 2022 |
| NT 10-Q | Filing | Aug 10, 2023 | Jun 30, 2023 |
| 8-K |
Current report
Restatement
|
Aug 10, 2023 | Aug 10, 2023 |
| 8-K/A |
Amended current report
Results of operations
|
Aug 10, 2023 | Aug 6, 2023 |
| 8-K |
Current report
Results of operations, Regulation FD disclosure
|
Aug 7, 2023 | Aug 6, 2023 |
| 8-K |
Current report
Officer or director change
|
Jun 28, 2023 | Jun 28, 2023 |
| 11-K | Employee savings plan report | Jun 28, 2023 | Dec 31, 2022 |
| 8-K |
Current report
Officer or director change
|
Jun 1, 2023 | May 26, 2023 |
| 8-K |
Current report
Officer or director change
|
May 30, 2023 | May 23, 2023 |
| SD | Specialized disclosure (conflict minerals) | May 26, 2023 | — |
| 8-K |
Current report
Shareholder vote results
|
May 15, 2023 | May 10, 2023 |
| 10-Q | Quarterly report | May 10, 2023 | Mar 31, 2023 |
| 8-K |
Current report
Results of operations
|
May 9, 2023 | May 8, 2023 |
| DEFA14A | Additional proxy material | May 3, 2023 | — |
| 8-K |
Current report
Results of operations
|
Apr 11, 2023 | Apr 10, 2023 |
| 8-K |
Current report
Officer or director change
|
Apr 3, 2023 | Mar 28, 2023 |
| 8-K |
Current report
Officer or director change
|
Mar 30, 2023 | Mar 27, 2023 |
| ARS | Annual report to shareholders | Mar 28, 2023 | Dec 31, 2022 |
| DEFA14A | Additional proxy material | Mar 28, 2023 | — |
| DEF 14A | Proxy statement | Mar 28, 2023 | — |
| 10-K | Annual report | Mar 1, 2023 | Dec 31, 2022 |
| 8-K |
Current report
Results of operations
|
Feb 21, 2023 | Feb 21, 2023 |
| 8-K |
Current report
Agreement ended
|
Feb 8, 2023 | Feb 6, 2023 |
| 8-K |
Current report
Officer or director change
|
Jan 26, 2023 | Jan 20, 2023 |
| 8-K |
Current report
Other events
|
Jan 19, 2023 | Jan 17, 2023 |
| S-3ASR | Automatic shelf registration | Dec 23, 2022 | — |
| 8-K |
Current report
Material agreement
|
Dec 5, 2022 | Dec 1, 2022 |
| 10-Q | Quarterly report | Nov 9, 2022 | Sep 30, 2022 |
| 8-K/A |
Amended current report
Results of operations
|
Nov 9, 2022 | Nov 7, 2022 |
| 8-K |
Current report
Results of operations
|
Nov 8, 2022 | Nov 7, 2022 |
| 8-K |
Current report
Other events
|
Oct 26, 2022 | Oct 24, 2022 |
| 8-K/A |
Amended current report
Results of operations
|
Oct 25, 2022 | Oct 24, 2022 |
| 8-K |
Current report
Results of operations
|
Oct 25, 2022 | Oct 24, 2022 |
| 8-K |
Current report
Other events
|
Oct 18, 2022 | Oct 18, 2022 |
| 8-K/A |
Amended current report
Officer or director change
|
Sep 30, 2022 | Jul 15, 2022 |
| 10-Q | Quarterly report | Aug 5, 2022 | Jun 30, 2022 |
| 8-K |
Current report
Results of operations
|
Aug 4, 2022 | Aug 3, 2022 |
| 8-K |
Current report
Material agreement, Agreement ended, New debt
|
Jul 22, 2022 | Jul 18, 2022 |
| 15-12G | Deregistration | Jul 21, 2022 | — |
| 8-K |
Current report
Acquisition or sale of assets, Officer or director change
|
Jul 15, 2022 | Jul 15, 2022 |
| S-8 | Employee stock plan registration | Jul 11, 2022 | — |
| S-8 | Employee stock plan registration | Jul 11, 2022 | — |
| 8-K12B | Filing | Jul 11, 2022 | Jul 8, 2022 |
| 25-NSE | Delisting notice | Jul 11, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| S-8 POS | Filing | Jul 8, 2022 | — |
| 425 | Filing | Jul 8, 2022 | — |
| 8-K |
Current report
Acquisition or sale of assets, Listing notice, Change to shareholder rights, Change in control, Officer or director change, Bylaw or fiscal year change, Regulation FD disclosure
|
Jul 8, 2022 | Jul 8, 2022 |
| 425 | Filing | Jul 7, 2022 | — |
| 8-K |
Current report
Regulation FD disclosure
|
Jul 7, 2022 | Jul 6, 2022 |
| 425 | Filing | Jul 7, 2022 | — |
| 425 | Filing | Jul 6, 2022 | — |
| 425 | Filing | Jul 6, 2022 | — |
| 425 | Filing | Jul 6, 2022 | — |
| 425 | Filing | Jul 6, 2022 | — |
| 8-K | Current report | Jun 30, 2022 | Jun 30, 2022 |
| 11-K | Employee savings plan report | Jun 28, 2022 | Dec 31, 2021 |
| SD | Specialized disclosure (conflict minerals) | May 27, 2022 | — |
| 8-K |
Current report
Material agreement, New debt
|
May 23, 2022 | May 19, 2022 |
| 8-K |
Current report
Shareholder vote results
|
May 13, 2022 | May 11, 2022 |
| 10-Q | Quarterly report | May 6, 2022 | Mar 31, 2022 |
| 8-K |
Current report
Results of operations
|
May 5, 2022 | May 4, 2022 |
| 8-K |
Current report
Material agreement, New debt
|
Apr 6, 2022 | Apr 1, 2022 |
| DEFA14A | Additional proxy material | Mar 29, 2022 | — |
| DEF 14A | Proxy statement | Mar 29, 2022 | May 11, 2022 |
| 10-K | Annual report | Feb 25, 2022 | Dec 31, 2021 |
| 425 | Filing | Feb 17, 2022 | — |
| 425 | Filing | Feb 17, 2022 | — |
| 8-K |
Current report
Results of operations
|
Feb 3, 2022 | Feb 2, 2022 |
| 425 | Filing | Jan 31, 2022 | — |
| 425 | Filing | Jan 31, 2022 | — |
| 425 | Filing | Jan 31, 2022 | — |
| 425 | Filing | Jan 26, 2022 | — |
| 425 | Filing | Jan 25, 2022 | — |
| 425 | Filing | Jan 25, 2022 | — |
| 425 | Filing | Jan 25, 2022 | — |
| 425 | Filing | Jan 24, 2022 | — |
| 425 | Filing | Jan 24, 2022 | — |
| 425 | Filing | Jan 24, 2022 | — |
| 425 | Filing | Jan 21, 2022 | — |
| 425 | Filing | Jan 20, 2022 | — |
| 425 | Filing | Jan 20, 2022 | — |
| 425 | Filing | Jan 14, 2022 | — |
| 425 | Filing | Jan 13, 2022 | — |
| 425 | Filing | Jan 13, 2022 | — |
| 425 | Filing | Jan 11, 2022 | — |
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)
Other Telephone & Telegraph Apparatus companies
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Source: SEC EDGAR filings. This is company-reported data, not investment advice.