NORTHWESTERN CORP SEC filing history

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SEC filing history

Showing 1–25 of 100 matching filings.

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15-12G File 001-10499

15-12G

Filing date
07 Dec 2023
Reporting date
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POSASR File 333-253047

POSASR

Filing date
02 Oct 2023
Reporting date
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POSASR File 333-257950

POSASR

Filing date
02 Oct 2023
Reporting date
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S-8 POS File 333-175813

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 333-149388

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 333-124624

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 333-122428

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 033-56401

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 333-11843

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 333-18991

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 333-80819

S-8 POS

Filing date
02 Oct 2023
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S-8 POS File 333-80817

S-8 POS

Filing date
02 Oct 2023
Reporting date
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25-NSE File 001-10499

25-NSE filing

Filing date
29 Sep 2023
Reporting date
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424B3 File 333-253047

SUPPLEMENT TO PROSPECTUS SUPPLEMENT

Filing date
15 Jun 2023
Reporting date
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144 File 001-10499

144 filing

Filing date
16 May 2023
Reporting date
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ARS File 001-10499

ARS

Filing date
14 Mar 2023
Reporting date
14 Mar 2023
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DEFA14A File 001-10499

DEFA14A

Filing date
14 Mar 2023
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DEFA14A File 001-10499

DEFA14A 2022 ANNUAL MTG NOTICE

Filing date
07 Mar 2022
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DEF 14A File 001-10499

DEF 14A

Filing date
07 Mar 2022
Reporting date
29 Apr 2022
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S-8 File 333-262705

S-8

Filing date
14 Feb 2022
Reporting date
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UPLOAD

UPLOAD filing

Filing date
10 Jan 2022
Reporting date
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CORRESP

CORRESP filing

Filing date
30 Dec 2021
Reporting date
Not listed
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UPLOAD

UPLOAD filing

Filing date
15 Dec 2021
Reporting date
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424B2 File 333-253047

424B5

Filing date
18 Nov 2021
Reporting date
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