Brian S. Posner - Insider Trading & Ownership

Location
14 Cambridge Center, Cambridge, MA
Summary
The estimated net worth of Brian S. Posner is at least $13.4M dollars as of October 2, 2025. Brian S. Posner is the Director of ARCH CAPITAL GROUP LTD. and owns shares of ARCH CAPITAL GROUP LTD. (ACGL) stock worth about $11.3M. Brian S. Posner is the Director of BIOGEN INC. and owns shares of BIOGEN INC. (BIIB) stock worth about $1.99M. Brian S. Posner is the Director of Dyne Therapeutics, Inc. and owns shares of Dyne Therapeutics, Inc. (DYN) stock worth about $107K.
Signature
/s/ Ron Caponigro, Attorney-in-Fact
All Insider Reports
All Insider Reports

Ownership of Brian S. Posner

Symbol Company Relationship Holdings Value Past Year Net Change Change % Report Period
ACGL, ACGLO ARCH CAPITAL GROUP LTD. Director $11.3M +$17.3K +0.15% Aug 1, 2025
BIIB BIOGEN INC. Director $1.99M Dec 31, 2022
DYN Dyne Therapeutics, Inc. Director $107K Oct 1, 2025

Insider Transactions Reported by Brian S. Posner:

Sym Company Class Transaction % Value $ * Price $ Shares Shares After Date Ownership
* An asterisk sign (*) next to the price indicates that the price is likely invalid.