ALLIANT ENERGY CORP — All Filings
1,002 total filings on record
Public companies registered with the SEC are required to file periodic reports, disclosures, and notices throughout the year. The most important are the 10-K (annual report), 10-Q (quarterly report), and 8-K (material event notice). Use the filters below to narrow by form type.
All
10-K
10-K/A
10-K405
10-K405/A
10-Q
10-Q/A
11-K
15-15D
25
3
3/A
35-CERT
35-CERT/A
4
4/A
424B2
424B3
424B5
5
5/A
8-A12B
8-A12B/A
8-K
8-K/A
ARS
CERT
CORRESP
CT ORDER
DEF 14A
DEFA14A
FWP
NO ACT
NT 10-K
NT 11-K
POS AMC
POSASR
PRE 14A
PX14A6G
RW
S-3
S-3/A
S-3ASR
S-3D
S-3MEF
S-4
S-4/A
S-8
S-8 POS
SC 13D
SC 13D/A
SC 13G
SC 13G/A
SCHEDULE 13G/A
SE
U-1
U-1/A
U-12-IB
U-13-60
U-57
U-6B-2
U-6B-2/A
U-9C-3
U5A
U5B
U5B/A
U5S
U5S/A
UPLOAD
| Form | Description | Accession Number | Filed | Period |
|---|---|---|---|---|
| SCHEDULE 13G/A | — | 0000102909-26-000581 | Mar 26, 2026 | — |
| 8-K | 8-K | 0001193125-26-116244 | Mar 19, 2026 | — |
| 424B5 | 424B5 | 0001193125-26-116238 | Mar 19, 2026 | — |
| 4/A | FORM 4/A | 0002105470-26-000005 | Mar 19, 2026 | Feb 19, 2026 |
| 3 | FORM 3 | 0002115951-26-000002 | Mar 4, 2026 | Feb 23, 2026 |
| 8-K | 8-K | 0000352541-26-000009 | Mar 4, 2026 | Mar 2, 2026 |
| 4 | FORM 4 | 0001541185-26-000004 | Feb 23, 2026 | Feb 19, 2026 |
| 4 | FORM 4 | 0002105470-26-000003 | Feb 23, 2026 | Feb 19, 2026 |
| 4 | FORM 4 | 0001763201-26-000001 | Feb 23, 2026 | Feb 19, 2026 |
| 4 | FORM 4 | 0001512789-26-000001 | Feb 23, 2026 | Feb 19, 2026 |
| 4 | FORM 4 | 0002022959-26-000001 | Feb 23, 2026 | Feb 19, 2026 |
| 4 | FORM 4 | 0001973120-26-000001 | Feb 23, 2026 | Feb 19, 2026 |
| 4 | FORM 4 | 0001936520-26-000001 | Feb 23, 2026 | Feb 19, 2026 |
| 4 | FORM 4 | 0002058131-26-000002 | Feb 23, 2026 | Feb 19, 2026 |
| 10-K | 10-K | 0000352541-26-000007 | Feb 20, 2026 | Dec 31, 2025 |
| 8-K | 8-K | 0000352541-26-000005 | Feb 20, 2026 | Feb 19, 2026 |
| S-8 POS | S-8 POS | 0001193125-26-042904 | Feb 9, 2026 | — |
| S-8 POS | S-8 POS | 0001193125-26-042896 | Feb 9, 2026 | — |
| S-8 POS | S-8 POS | 0001193125-26-042889 | Feb 9, 2026 | — |
| S-8 POS | S-8 POS | 0001193125-26-042875 | Feb 9, 2026 | — |
| S-8 POS | S-8 POS | 0001193125-26-042871 | Feb 9, 2026 | — |
| S-8 POS | S-8 POS | 0001193125-26-042861 | Feb 9, 2026 | — |
| S-8 POS | S-8 POS | 0001193125-26-042857 | Feb 9, 2026 | — |
| 3 | FORM 3 | 0002105470-26-000002 | Jan 15, 2026 | Jan 5, 2026 |
| 4 | FORM 4 | 0001191569-26-000002 | Jan 12, 2026 | Jan 9, 2026 |
| 4 | FORM 4 | 0001654634-26-000001 | Jan 12, 2026 | Jan 9, 2026 |
| 4 | FORM 4 | 0001463371-26-000001 | Jan 12, 2026 | Jan 9, 2026 |
| 4 | FORM 4 | 0001684665-26-000001 | Jan 12, 2026 | Jan 9, 2026 |
| 4 | FORM 4 | 0001607542-26-000001 | Jan 12, 2026 | Jan 9, 2026 |
| 4 | FORM 4 | 0001298509-26-000001 | Jan 12, 2026 | Jan 9, 2026 |
| 4 | FORM 4 | 0001942745-26-000001 | Jan 12, 2026 | Jan 9, 2026 |
| 8-K | 8-K | 0000352541-26-000003 | Jan 8, 2026 | Jan 5, 2026 |
| 8-K | 8-K | 0000352541-25-000089 | Dec 16, 2025 | Dec 10, 2025 |
| 8-K | 8-K | 0000352541-25-000085 | Dec 5, 2025 | Dec 2, 2025 |
| 10-Q | 10-Q | 0000352541-25-000081 | Nov 7, 2025 | Sep 30, 2025 |
| 8-K | 8-K | 0000352541-25-000079 | Nov 7, 2025 | Nov 6, 2025 |
| 4 | FORM 4 | 0001298509-25-000003 | Oct 14, 2025 | Oct 10, 2025 |
| 4 | FORM 4 | 0001607542-25-000003 | Oct 14, 2025 | Oct 10, 2025 |
| 4 | FORM 4 | 0001942745-25-000002 | Oct 14, 2025 | Oct 10, 2025 |
| 4 | FORM 4 | 0001684665-25-000003 | Oct 14, 2025 | Oct 10, 2025 |
| 4 | FORM 4 | 0001463371-25-000002 | Oct 14, 2025 | Oct 10, 2025 |
| 4 | FORM 4 | 0001654634-25-000004 | Oct 14, 2025 | Oct 10, 2025 |
| 8-K | 8-K | 0000352541-25-000076 | Sep 26, 2025 | Sep 23, 2025 |
| 424B5 | 424B5 | 0001193125-25-216952 | Sep 25, 2025 | — |
| FWP | FWP | 0001193125-25-213616 | Sep 23, 2025 | — |
| 424B5 | 424B5 | 0001193125-25-212360 | Sep 23, 2025 | — |
| POSASR | POSASR | 0001193125-25-210261 | Sep 22, 2025 | — |
| 8-K | 8-K | 0000352541-25-000074 | Sep 11, 2025 | Sep 8, 2025 |
| 10-Q | 10-Q | 0000352541-25-000072 | Aug 8, 2025 | Jun 30, 2025 |
| 8-K | 8-K | 0000352541-25-000070 | Aug 8, 2025 | Aug 7, 2025 |