Filer Snapshot

William P. Stiritz

CIK 0001052058. SEC filing timeline plus parsed ownership intelligence from 13F, 13D/G, and Forms 3/4/5 where available.

Entity type

Individual

Total filings

31

Latest filing

05 Mar 2026

Industry

n/a

Filing-backed research brief

Start with the SEC data that changes for this CIK

Latest signal: 13D/G stake for POST. Each card links back to the PortfolioSavvy page where the filing evidence is closest.

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Largest parsed holding

—

Populates from the latest parsed 13F information table.

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13D/G large stake

POST

04 Mar 2026 · 10% ownership

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Source: SEC Schedule 13D/G

SCHEDULE 13D/A filed on 05 Mar 2026 for CIK 0001052058.

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Ownership signals CIK-linked ownership evidence from parsed SEC filings. 1 signal
Parsed SEC ownership signals

Parsed SEC ownership coverage

These bars compare filing-backed value available in each disclosure family. Read them as separate lenses, not as one combined ownership total.

Forms 3/4/5 positions$518.25M

Reporting-owner positions with enough filing detail to estimate value.

Forms 3/4/5 position value

3/4/5
$518.25M

Estimated from parsed Forms 3/4/5 when filings include enough share and price data.

Largest linked holdings

Largest issuer positions linked to this CIK across parsed 13F, 13D/G, and Forms 3/4/5 records.

POST

Largest active 13D stakes

Active large-stake positions disclosed in parsed Schedule 13D filings.

POST
How to read these SEC ownership signals
  • Read each filing family separately: 13F portfolios, 13D/G large stakes, and Forms 3/4/5 owner positions answer different SEC disclosure questions.
  • Open the linked research path when you need the filing, CIK, issuer, or CUSIP trail behind a value.
At a glance Names, identifiers, and filing context for this profile. 1 identity field
Business address
C/O Post Holdings, Inc., 2503 S. Hanley Road, St Louis, MO, 63144

Filer intelligence

What SEC filings say about William P. Stiritz

A compact read of parsed XML filings. 13F, 13D/G, and Forms 3/4/5 are shown separately because they answer different ownership questions.

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Quick read

  • 1 recent 13D/G stake row found; top row is POST at 10% ownership.
  • Forms 3/4/5 show insider context for POST worth $518.25M.

SEC source mix

Counts show available parsed rows, not one combined ownership total.

XML parsed
13F portfolio No rows yet

Quarterly institutional portfolio holdings.

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13D/G stakes 1 rows

Beneficial ownership and large-stake disclosures.

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Forms 3/4/5 1 rows

Officer, director, and 10% owner holdings or transactions.

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13D/G large-stake context

POST

04 Mar 2026 · Common Stock, $0.01 par value

10%
Issuer page 13D/G history

Forms 3/4/5 insider context

POST

17 Dec 2025

$518.25M
Issuer page Owner page

Latest update

What changed recently for William P. Stiritz

New filing available

Latest Schedule 13D/G period: 04 Mar 2026. Open the source-backed page to inspect the fresh filing or facts context.

Update date

05 Mar 2026

Page type

Filer profile

Latest period

04 Mar 2026

Schedule 13D/G context is visible from filings filed on 05 Mar 2026.

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SEC filing record

CIK 0001052058 filing coverage

Start with this filing record, then use the linked ownership pages when parsed 13F, 13D/G, Forms 3/4/5, or facts data exists for this CIK.

SEC filings
31
First seen
02 Jun 2021
Latest filing
05 Mar 2026
Entity
Individual

Observed form types

4 SCHEDULE 13D/A

CIK-linked evidence first

William P. Stiritz SEC filings William P. Stiritz 13D/G history William P. Stiritz owner filings Open SEC filing index

Latest Filings

Showing the latest 12 of 31 SEC filings for William P. Stiritz.

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SCHEDULE 13D/A

SCHEDULE 13D/A filing

Filing date
05 Mar 2026
Reporting date
Not listed
SEC evidence
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4

4 filing

Filing date
04 Nov 2025
Reporting date
31 Oct 2025
SEC evidence
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SCHEDULE 13D/A

SCHEDULE 13D/A filing

Filing date
15 Oct 2025
Reporting date
Not listed
SEC evidence
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SCHEDULE 13D/A

SCHEDULE 13D/A filing

Filing date
14 Feb 2025
Reporting date
Not listed
SEC evidence
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4

4 filing

Filing date
02 Aug 2023
Reporting date
31 Jul 2023
SEC evidence
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4

4 filing

Filing date
05 Jul 2023
Reporting date
30 Jun 2023
SEC evidence
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4

4 filing

Filing date
01 Jun 2023
Reporting date
31 May 2023
SEC evidence
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4

4 filing

Filing date
01 May 2023
Reporting date
28 Apr 2023
SEC evidence
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4

4 filing

Filing date
04 Apr 2023
Reporting date
31 Mar 2023
SEC evidence
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4

4 filing

Filing date
01 Mar 2023
Reporting date
28 Feb 2023
SEC evidence
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4

4 filing

Filing date
02 Feb 2023
Reporting date
31 Jan 2023
SEC evidence
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4

4 filing

Filing date
03 Jan 2023
Reporting date
30 Dec 2022
SEC evidence
Open document Open filing
Next action
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