Alliant Energy Corp SEC filings LNT
Alliant Energy Corp has 1,000 filings in SEC EDGAR's recent list, going back to Jan 31, 2014. Its latest annual report, Form ARS, was filed on Mar 31, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Oct 30, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Oct 30, 2026 (results of operations). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| DEFA14A | Additional proxy material | Mar 31, 2026 | — |
| DEF 14A | Proxy statement | Mar 31, 2026 | May 20, 2026 |
| DEFA14A | Additional proxy material | Apr 1, 2025 | — |
| DEF 14A | Proxy statement | Apr 1, 2025 | May 16, 2025 |
| DEFA14A | Additional proxy material | Apr 2, 2024 | — |
| DEF 14A | Proxy statement | Apr 2, 2024 | May 17, 2024 |
| DEFA14A | Additional proxy material | Apr 4, 2023 | — |
| DEF 14A | Proxy statement | Apr 4, 2023 | — |
| DEFA14A | Additional proxy material | Mar 31, 2022 | — |
| DEF 14A | Proxy statement | Mar 31, 2022 | May 19, 2022 |
| DEFA14A | Additional proxy material | Apr 1, 2021 | — |
| DEF 14A | Proxy statement | Apr 1, 2021 | May 20, 2021 |
| DEFA14A | Additional proxy material | Apr 9, 2020 | — |
| DEF 14A | Proxy statement | Apr 9, 2020 | May 21, 2020 |
| DEF 14A | Proxy statement | Apr 8, 2019 | May 16, 2019 |
| DEF 14A | Proxy statement | Apr 9, 2018 | May 17, 2018 |
| DEFA14A | Additional proxy material | May 8, 2017 | — |
| DEFA14A | Additional proxy material | Apr 20, 2017 | — |
| DEF 14A | Proxy statement | Apr 18, 2017 | May 23, 2017 |
| DEF 14A | Proxy statement | Mar 31, 2016 | May 13, 2016 |
| DEF 14A | Proxy statement | Mar 24, 2015 | May 7, 2015 |
| DEF 14A | Proxy statement | Apr 3, 2014 | May 13, 2014 |
Showing 22 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
- Electric & Other Services Combined (SIC 4931)
- Listed as
- LNT (Nasdaq)
- Fiscal year ends
- December 31
- Incorporated in
- WI
- Headquarters
- Madison, WI
- SEC filer status
- Large accelerated filer
- SEC CIK
- 352541
- Former names
- ALLIANT ENERGY CORP (until Oct 30, 2026); INTERSTATE ENERGY CORP (until May 13, 1999); WPL HOLDINGS INC (until Feb 23, 1998)
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Source: SEC EDGAR filings. This is company-reported data, not investment advice.