Filer Snapshot

Michael Stuart Klein

CIK 0001327392. SEC filing timeline plus parsed ownership intelligence from 13F, 13D/G, and Forms 3/4/5 where available.

Entity type

Individual

Total filings

12

Latest filing

11 Sep 2025

Industry

n/a

Filing-backed research brief

Start with the SEC data that changes for this CIK

Latest signal: 13D/G stake for CCCX. 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

CCCX

08 Sep 2025 · 20% ownership

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Source: SEC Schedule 13D/G

SCHEDULE 13D/A filed on 11 Sep 2025 for CIK 0001327392.

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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$308.72M

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

Forms 3/4/5 position value

3/4/5
$308.72M

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.

CCXIU CCCX OKLO SKIL CTEV

Largest active 13D stakes

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

CCCX
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 Davis Polk & Wardwell, 450 Lexington Avenue, New York, NY, 10017

Filer intelligence

What SEC filings say about Michael Stuart Klein

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 CCCX at 20% ownership.
  • Forms 3/4/5 show insider context for CCXIU worth $143M.

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 5 rows

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

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13D/G large-stake context

CCCX

08 Sep 2025 · Class A Ordinary Shares, $0.0001 par value

20%
Issuer page 13D/G history

Forms 3/4/5 insider context

CCXIU

18 Dec 2025 · See Remarks · 10% owner

$143M
Issuer page Owner page

CCCX

12 Feb 2026 · See Remarks · 10% owner

$133.02M
Issuer page Owner page

OKLO

22 Sep 2025 · 10% owner

$20.28M
Issuer page Owner page

SKIL

17 Jul 2025

$8.83M
Issuer page Owner page

Latest update

What changed recently for Michael Stuart Klein

Ownership report updated

Latest ownership report period: 29 Apr 2026. Open the source-backed page to inspect the fresh filing or facts context.

Update date

01 May 2026

Page type

Ownership filings

Latest period

29 Apr 2026

Ownership context was refreshed from SEC Forms 3/4/5 filed on 01 May 2026.

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SEC filing record

CIK 0001327392 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
12
First seen
01 Jun 2021
Latest filing
11 Sep 2025
Entity
Individual

Observed form types

3 4 SCHEDULE 13D SCHEDULE 13D/A

CIK-linked evidence first

Michael Stuart Klein SEC filings Michael Stuart Klein 13D/G history Michael Stuart Klein owner filings Open SEC filing index

Latest Filings

Showing the latest 12 of 12 SEC filings for Michael Stuart Klein.

SCHEDULE 13D/A

SCHEDULE 13D/A filing

Filing date
11 Sep 2025
Reporting date
Not listed
SEC evidence
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SCHEDULE 13D

SCHEDULE 13D filing

Filing date
21 May 2025
Reporting date
Not listed
SEC evidence
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4

4 filing

Filing date
24 Jul 2023
Reporting date
20 Jul 2023
SEC evidence
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4

4 filing

Filing date
23 Jun 2023
Reporting date
23 Jun 2023
SEC evidence
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4

4 filing

Filing date
28 Apr 2023
Reporting date
26 Apr 2023
SEC evidence
Open document Open filing
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4

4 filing

Filing date
24 Jun 2022
Reporting date
23 Jun 2022
SEC evidence
Open document Open filing
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4

4 filing

Filing date
28 Apr 2022
Reporting date
26 Apr 2022
SEC evidence
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4

4 filing

Filing date
30 Dec 2021
Reporting date
28 Dec 2021
SEC evidence
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4

4 filing

Filing date
14 Jul 2021
Reporting date
12 Jul 2021
SEC evidence
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3

3 filing

Filing date
07 Jul 2021
Reporting date
07 Jul 2021
SEC evidence
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4

4 filing

Filing date
14 Jun 2021
Reporting date
11 Jun 2021
SEC evidence
Open document Open filing
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4

4 filing

Filing date
01 Jun 2021
Reporting date
27 May 2021
SEC evidence
Open document Open filing
Next action
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