Filer Snapshot

Brian S. Posner SEC EDGAR Filings

SEC filings, ownership reports, and insider transactions for CIK 0001372455.

Entity Type

Individual

Total Filings

88

Latest Filing

01 Apr 2026

Industry

n/a

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Go to latest filings table Open reporting owner context
Source: SEC Forms 3/4/5

4 filed on 01 Apr 2026 for CIK 0001372455.

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Business address
14 Cambridge Center, Cambridge, MA, 02142
Top holdings (ownership)
ACGL, BIIB, and DYN

Quick Takeaways

  • Brian S. Posner is an SEC filer tracked under CIK 0001372455.
  • 88 filings are listed on this profile.
  • Common form coverage includes 4, 3, 5 and more.

What Changed

  • Latest filing: 4 filed on 01 Apr 2026.
  • Report period: 30 Mar 2026.

Why This Matters

  • You can quote filing dates and form types directly from the SEC record on this page.
  • Use this profile before deeper ownership or insider analysis to confirm filing history context.

Source Evidence

Source: SEC Forms 3/4/5

4 filed on 01 Apr 2026 for CIK 0001372455.

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Return Loop

Why revisit this filer page

A newly filed 4 can change the filing history, ownership context, or next research path for Brian S. Posner.

Latest source-backed update
4 filed 01 Apr 2026
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Revisit after a new SEC filing appears to compare the updated record with prior filings.
  • Latest filing on record: 4 filed 01 Apr 2026.
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Filer freshness comes from SEC EDGAR submission history and related source-backed ownership or portfolio filings when available.

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Latest update

What changed recently for Brian S. Posner

Ownership report updated

Latest ownership report period: 30 Mar 2026. Open the source-backed page to inspect the fresh filing or facts context.

Update date

01 Apr 2026

Page type

Ownership filings

Latest period

30 Mar 2026

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

Open ownership filings Browse recent public updates

Filer Overview

Brian S. Posner has filed 88 SEC EDGAR filings since 11 Aug 2006. Common forms include 4, 3, 5, 4/A.

Reporting owner transactions Latest 13F filings

Latest Filings

Recent SEC filings for Brian S. Posner with direct links to document and filing folders.

Form type Document Filing Description Filing date Reporting date File number(s)
4 Open 4 document View SEC filing for 4 4 01 Apr 2026 30 Mar 2026 001-39509
4 Open 4 document View SEC filing for 4 4 13 Mar 2026 11 Mar 2026 001-39509
4 Open 4 document View SEC filing for 4 FORM 4 12 Mar 2026 11 Mar 2026 001-16209
4 Open 4 document View SEC filing for 4 4 10 Mar 2026 06 Mar 2026 001-39509
4 Open 4 document View SEC filing for 4 4 02 Oct 2025 01 Oct 2025 001-39509
3 Open 3 document View SEC filing for 3 3 02 Oct 2025 01 Oct 2025 001-39509
4 Open 4 document View SEC filing for 4 04 Aug 2025 01 Aug 2025 001-16209
4 Open 4 document View SEC filing for 4 09 May 2025 07 May 2025 001-16209
4 Open 4 document View SEC filing for 4 13 May 2024 09 May 2024 001-16209
4 Open 4 document View SEC filing for 4 08 May 2023 04 May 2023 001-16209
5 Open 5 document View SEC filing for 5 PRIMARY DOCUMENT 27 Jan 2023 31 Dec 2022 000-19311
4 Open 4 document View SEC filing for 4 01 Nov 2022 28 Oct 2022 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 06 May 2022 04 May 2022 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 02 May 2022 29 Apr 2022 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 01 Oct 2021 30 Sep 2021 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 02 Jul 2021 01 Jul 2021 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 15 Jun 2021 14 Jun 2021 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 07 Jun 2021 04 Jun 2021 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 10 May 2021 06 May 2021 001-16209
5 Open 5 document View SEC filing for 5 PRIMARY DOCUMENT 09 Feb 2021 31 Dec 2020 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 05 Jun 2020 03 Jun 2020 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 15 May 2020 13 May 2020 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 08 May 2020 06 May 2020 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 03 Dec 2019 02 Dec 2019 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 20 Jun 2019 19 Jun 2019 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 09 May 2019 08 May 2019 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 15 Feb 2019 14 Feb 2019 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 29 Nov 2018 28 Nov 2018 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 06 Nov 2018 05 Nov 2018 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 14 Jun 2018 12 Jun 2018 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 10 May 2018 09 May 2018 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 04 May 2018 03 May 2018 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 08 Mar 2018 08 Mar 2018 001-37859
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 02 Feb 2018 31 Jan 2018 001-37859
4 Open 4 document View SEC filing for 4 FORM 4 - 02 Jan 2018 02 Jan 2018 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 26 Sep 2017 25 Sep 2017 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 19 Sep 2017 18 Sep 2017 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 10 Aug 2017 09 Aug 2017 001-37859
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 12 Jun 2017 09 Jun 2017 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 09 Jun 2017 07 Jun 2017 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 24 May 2017 24 May 2017 001-37859
4 Open 4 document View SEC filing for 4 FORM 4 - 05 May 2017 04 May 2017 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 17 Apr 2017 17 Apr 2017 001-37859
4/A Open 4/A document View SEC filing for 4/A PRIMARY DOCUMENT 27 Mar 2017 14 Feb 2017 001-37859
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 16 Feb 2017 14 Feb 2017 001-37859
3 Open 3 document View SEC filing for 3 PRIMARY DOCUMENT 19 Jan 2017 10 Jan 2017 001-37859
4 Open 4 document View SEC filing for 4 FORM 4 - 21 Nov 2016 18 Nov 2016 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 09 Jun 2016 08 Jun 2016 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 09 May 2016 06 May 2016 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 23 Jun 2015 22 Jun 2015 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 16 Jun 2015 15 Jun 2015 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 11 Jun 2015 10 Jun 2015 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 11 May 2015 07 May 2015 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 10 Feb 2015 06 Feb 2015 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 25 Jul 2014 24 Jul 2014 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 23 Jun 2014 20 Jun 2014 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 16 Jun 2014 12 Jun 2014 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - BRIAN POSNER 05 Jun 2014 03 Jun 2014 001-33827
4 Open 4 document View SEC filing for 4 FORM 4 - 13 May 2014 09 May 2014 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 01 Apr 2014 31 Mar 2014 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 20 Aug 2013 19 Aug 2013 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 05 Aug 2013 02 Aug 2013 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - BRIAN S. POSNER 14 Jun 2013 12 Jun 2013 001-33827
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 13 Jun 2013 11 Jun 2013 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 13 May 2013 09 May 2013 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 19 Mar 2013 18 Mar 2013 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - BRIAN S. POSNER 20 Nov 2012 19 Nov 2012 001-33827
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 11 Jun 2012 08 Jun 2012 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 11 Jun 2012 07 Jun 2012 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 05 Jun 2012 04 Jun 2012 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - BRIAN S. POSNER 23 May 2012 22 May 2012 001-33827
4 Open 4 document View SEC filing for 4 FORM 4 - 11 May 2012 09 May 2012 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - BRIAN S. POSNER 15 Feb 2012 13 Feb 2012 001-33827
3 Open 3 document View SEC filing for 3 FORM 3 - BRIAN S. POSNER 15 Feb 2012 13 Feb 2012 001-33827
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 31 Aug 2011 29 Aug 2011 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 SUBMISSION 24 Aug 2011 22 Aug 2011 000-50632
3 Open 3 document View SEC filing for 3 FORM 3 SUBMISSION 24 Aug 2011 22 Aug 2011 000-50632
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 02 Jun 2011 01 Jun 2011 000-19311
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 27 May 2011 25 May 2011 000-19311
4 Open 4 document View SEC filing for 4 FORM 4 - 09 May 2011 06 May 2011 001-16209
4 Open 4 document View SEC filing for 4 FORM 4 - 08 Nov 2010 04 Nov 2010 001-16209
3 Open 3 document View SEC filing for 3 FORM 3 - 08 Nov 2010 04 Nov 2010 001-16209
4 Open 4 document View SEC filing for 4 PRIMARY DOCUMENT 10 Jun 2010 09 Jun 2010 000-19311

About this filer

Brian S. Posner files with the SEC under CIK 0001372455. This page aggregates EDGAR filings and related ownership activity.

FAQ

What is a CIK?
A Central Index Key (CIK) is a unique identifier assigned by the SEC to each filer.
Why are some filings missing?
New filings appear as the SEC updates EDGAR, and older records can vary by availability.
How often is this page updated?
Updates follow new EDGAR submissions and periodic data refreshes.