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 |
|---|---|---|---|
| 11-K | Employee savings plan report | Jun 26, 2026 | Dec 31, 2025 |
| SD | Specialized disclosure (conflict minerals) | May 12, 2026 | — |
| 11-K | Employee savings plan report | Jun 30, 2025 | Dec 31, 2024 |
| ARS/A | Filing | Jun 6, 2025 | Dec 31, 2024 |
| DEFR14A | Filing | Jun 6, 2025 | — |
| SD | Specialized disclosure (conflict minerals) | May 29, 2025 | — |
| NT 10-Q | Filing | May 13, 2025 | May 13, 2025 |
| EFFECT | Filing | Nov 26, 2024 | — |
| CORRESP | Letter to the SEC | Nov 22, 2024 | — |
| UPLOAD | Letter from the SEC | Nov 21, 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 | — |
| 11-K | Employee savings plan report | Jun 28, 2024 | Dec 31, 2023 |
| SD | Specialized disclosure (conflict minerals) | May 22, 2024 | — |
| NT 10-K | Filing | Feb 29, 2024 | Dec 31, 2023 |
| NT 10-Q | Filing | Aug 10, 2023 | Jun 30, 2023 |
| 11-K | Employee savings plan report | Jun 28, 2023 | Dec 31, 2022 |
| SD | Specialized disclosure (conflict minerals) | May 26, 2023 | — |
| 15-12G | Deregistration | Jul 21, 2022 | — |
| 8-K12B | Filing | Jul 11, 2022 | Jul 8, 2022 |
| 25-NSE | Delisting notice | Jul 11, 2022 | — |
| 425 | Filing | Jul 8, 2022 | — |
| 425 | Filing | Jul 7, 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 | — |
| 11-K | Employee savings plan report | Jun 28, 2022 | Dec 31, 2021 |
| SD | Specialized disclosure (conflict minerals) | May 27, 2022 | — |
| 425 | Filing | Feb 17, 2022 | — |
| 425 | Filing | Feb 17, 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 | — |
| 425 | Filing | Jan 11, 2022 | — |
| 425 | Filing | Jan 11, 2022 | — |
| 425 | Filing | Jan 11, 2022 | — |
| 425 | Filing | Jan 7, 2022 | — |
| 425 | Filing | Jan 7, 2022 | — |
| 425 | Filing | Jan 7, 2022 | — |
| 425 | Filing | Jan 7, 2022 | — |
| 425 | Filing | Jan 6, 2022 | — |
| 425 | Filing | Jan 5, 2022 | — |
| 425 | Filing | Jan 3, 2022 | — |
| 425 | Filing | Dec 28, 2021 | — |
| 425 | Filing | Dec 27, 2021 | — |
| 425 | Filing | Dec 23, 2021 | — |
| 425 | Filing | Dec 22, 2021 | — |
| 425 | Filing | Dec 20, 2021 | — |
| 425 | Filing | Dec 17, 2021 | — |
| 425 | Filing | Dec 17, 2021 | — |
| 425 | Filing | Dec 17, 2021 | — |
| 425 | Filing | Dec 17, 2021 | — |
| 425 | Filing | Dec 13, 2021 | — |
| 425 | Filing | Dec 13, 2021 | — |
| 425 | Filing | Dec 8, 2021 | — |
| 425 | Filing | Dec 7, 2021 | — |
| 425 | Filing | Dec 7, 2021 | — |
| 425 | Filing | Nov 24, 2021 | — |
| 425 | Filing | Nov 24, 2021 | — |
| 425 | Filing | Nov 23, 2021 | — |
| 425 | Filing | Nov 12, 2021 | — |
| 425 | Filing | Nov 12, 2021 | — |
| 425 | Filing | Nov 2, 2021 | — |
| 425 | Form 425 | Nov 2, 2021 | — |
| 425 | Filing | Nov 2, 2021 | — |
| 425 | Filing | Aug 31, 2021 | — |
| 425 | Filing | Aug 31, 2021 | — |
| 425 | Filing | Aug 31, 2021 | — |
| 425 | Filing | Aug 31, 2021 | — |
| 425 | Filing | Aug 31, 2021 | — |
| 425 | Filing | Aug 31, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 425 | Filing | Aug 30, 2021 | — |
| 11-K | Employee savings plan report | Jun 29, 2021 | Dec 31, 2020 |
| SD | Specialized disclosure (conflict minerals) | May 21, 2021 | — |
| 11-K | Employee savings plan report | Jun 29, 2020 | Dec 31, 2019 |
| SD | Specialized disclosure (conflict minerals) | May 28, 2020 | — |
| NT 10-Q | Filing | Aug 12, 2019 | Jun 30, 2019 |
| 11-K | Employee savings plan report | Jun 27, 2019 | Dec 31, 2018 |
| SD | Specialized disclosure (conflict minerals) | May 30, 2019 | — |
| 11-K | Employee savings plan report | Jun 27, 2018 | Dec 31, 2017 |
| SD | Specialized disclosure (conflict minerals) | May 31, 2018 | — |
| UPLOAD | Letter from the SEC | Oct 31, 2017 | — |
| CORRESP | Letter to the SEC | Oct 18, 2017 | — |
| CORRESP | Letter to the SEC | Sep 18, 2017 | — |
| UPLOAD | Letter from the SEC | Sep 12, 2017 | — |
Showing 116 filings. 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.