Brian S Posner

CIK 1372455 · last filed 2026-06-09

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$2.08M

Companies

9

Total Filings

80

Lifetime Open-Market Net

-$5.72M

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
DYN Director 24,500 $18.19 $445.7K $274.8K 8 2026-06-09
ACGLO Director 0 $19.33 $0 $208.3K 21 2026-06-04
BIIB Director 8,175 $200.05 $1.64M -$6.74M 26 2021-07-02
Bioverativ Inc. (BIVV) Delisted Director 0 $166.9K 7 2018-03-08
ARCH CAPITAL GROUP LTD. (ARHpC.CL) Delisted Director 6,000 $0 1 2018-01-02
ARCH CAPITAL GROUP LTD. (ARHpC) Delisted Director 6,000 $316.4K 10 2017-09-26
BG Medicine, Inc. (BGMD) Delisted Director 20,000 $52.0K 4 2013-06-14
ANADYS PHARMACEUTICALS INC (ANDS) Delisted Director $0 1 2011-08-24
ARCH CAPITAL GROUP LTD. (ARHpB) Delisted Director 1,658 $0 2 2011-05-09

Recent Filings · Page 2 of 8

80 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2026-03-10 DYN Buy (P) +3,000 $45.2K EDGAR
2025-10-02 DYN Grant (A) $0 EDGAR
2025-08-04 ACGLO Buy (P) +1,000 $17.3K EDGAR
2025-05-09 ACGLO Grant (A) +1,564 $0 EDGAR
2024-05-13 ACGLO Grant (A) +1,455 $0 EDGAR
2023-05-08 ACGLO Grant (A) +1,714 $0 EDGAR
2022-11-01 ACGLO Buy (P) +2,000 $35.2K EDGAR
2022-05-06 ACGLO Grant (A) +5,284 $0 EDGAR
2022-05-02 ACGLO Buy (P) +2,000 $38.5K EDGAR
2021-10-01 ACGLO Disp (D) −2,000 -$50.0K EDGAR
Showing 1120 of 80
Page 2 of 8
Codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.