LNT · CIK 0000352541
ALLIANT ENERGY CORP (LNT) SEC Filings
Browse 3116 SEC filings for ALLIANT ENERGY CORP, covering Feb 7, 1994 through Jul 14, 2026, organized by filing purpose with direct links to the original EDGAR documents.
Indexed filings
3,116
Filed in the last 12 months
81
History covered
1994–2026
Latest filing
4
Latest important filings
Jump directly to the most recent annual, quarterly, and current reports.
Latest annual report
10-K
Annual report · Feb 20, 2026
Open original filingLatest quarterly report
10-Q
Quarterly report · May 1, 2026
Open original filingLatest company update
8-K
Shareholder vote · May 21, 2026
Open original filingComplete filing history
Search by form or description, filter by purpose and year, and open the original SEC document.
50 filings
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| Form | Description | Period ended | Filed |
|---|---|---|---|
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 4 | Change in insider ownership | Jul 10, 2026 | Jul 14, 2026 |
| 11-K | Employee benefit plan annual report | Dec 31, 2025 | Jun 16, 2026 |
| 8-K | Shareholder vote | May 20, 2026 | May 21, 2026 |
| 10-Q | Quarterly report | Mar 31, 2026 | May 1, 2026 |
| 8-K | Results of operations | Apr 30, 2026 | May 1, 2026 |
| SCHEDULE 13G | SCHEDULE 13G filing | — | Apr 29, 2026 |
| SCHEDULE 13G | SCHEDULE 13G filing | — | Apr 28, 2026 |
| 4 | Change in insider ownership | Apr 15, 2026 | Apr 16, 2026 |
| 4 | Change in insider ownership | Apr 10, 2026 | Apr 14, 2026 |
| 4 | Change in insider ownership | Apr 10, 2026 | Apr 14, 2026 |
| 4 | Change in insider ownership | Apr 10, 2026 | Apr 14, 2026 |
| 4 | Change in insider ownership | Apr 10, 2026 | Apr 14, 2026 |
| 4 | Change in insider ownership | Apr 10, 2026 | Apr 14, 2026 |
| 4 | Change in insider ownership | Apr 10, 2026 | Apr 14, 2026 |
| 4 | Change in insider ownership | Apr 10, 2026 | Apr 14, 2026 |
| ARS | ARS filing | Dec 31, 2025 | Mar 31, 2026 |
| DEFA14A | Additional proxy materials | — | Mar 31, 2026 |
| DEF 14A | Definitive proxy statement | May 20, 2026 | Mar 31, 2026 |
Page 1 of 2
Recent filing activity
Annual filing counts derived from this company's SEC history.
2026
57 filings
2025
63 filings
2024
65 filings
2023
69 filings
2022
68 filings
2021
68 filings
2020
68 filings
2019
67 filings
Sources and methodology
How this filing index is assembled and checked.
Filing metadata comes from SEC EDGAR submissions. Categories and plain-language labels are generated deterministically from SEC form and item codes; filing content is not summarized on this page.
Index updated: 7/15/2026
For research and education only. Always review the original SEC filing before making a decision.