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 |
|---|---|---|---|
| DEFA14A | Additional proxy material | May 1, 2026 | — |
| 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 |
| DEFA14A | Additional proxy material | Jun 6, 2025 | — |
| DEFA14A | Additional proxy material | May 27, 2025 | — |
| DEFA14A | Additional proxy material | May 13, 2025 | — |
| DEFA14A | Additional proxy material | Mar 31, 2025 | — |
| DEF 14A | Proxy statement | Mar 31, 2025 | Mar 31, 2025 |
| DEFA14A | Additional proxy material | Apr 4, 2024 | — |
| DEFA14A | Additional proxy material | Mar 27, 2024 | — |
| DEF 14A | Proxy statement | Mar 27, 2024 | May 8, 2024 |
| DEFA14A | Additional proxy material | May 3, 2023 | — |
| DEFA14A | Additional proxy material | Mar 28, 2023 | — |
| DEF 14A | Proxy statement | Mar 28, 2023 | — |
| DEFA14A | Additional proxy material | Mar 29, 2022 | — |
| DEF 14A | Proxy statement | Mar 29, 2022 | May 11, 2022 |
| DEFM14A | Filing | Dec 2, 2021 | — |
| DEFA14A | Additional proxy material | Mar 30, 2021 | — |
| DEF 14A | Proxy statement | Mar 30, 2021 | May 12, 2021 |
| DEFA14A | Additional proxy material | Apr 13, 2020 | — |
| DEFA14A | Additional proxy material | Apr 2, 2020 | — |
| DEF 14A | Proxy statement | Apr 2, 2020 | May 13, 2020 |
| DEF 14A | Proxy statement | Apr 3, 2019 | May 8, 2019 |
| DEF 14A | Proxy statement | Apr 4, 2018 | May 9, 2018 |
Showing 25 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.