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 3 of 8
80 filingsForm 4 transactions across all companies, newest first.
| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2021-07-02 | BIIB | Grant (A) | +775 | $0 | EDGAR |
| 2021-06-15 | ACGLO | Sell (S) | −4,000 | -$101.0K | EDGAR |
| 2021-06-07 | BIIB | Sell (S) | −360 | -$98.7K | EDGAR |
| 2021-05-10 | ACGLO | Grant (A) | +6,286 | $0 | EDGAR |
| 2020-06-05 | BIIB | Grant (A) | +890 | $0 | EDGAR |
| 2020-05-15 | ACGLO | Buy (P) | +1,000 | $22.2K | EDGAR |
| 2020-05-08 | ACGLO | Mixed | +11,116 | $23.7K | EDGAR |
| 2019-12-03 | BIIB | Sell (S) | −1,055 | -$308.4K | EDGAR |
| 2019-06-20 | BIIB | Grant (A) | +1,155 | $0 | EDGAR |
| 2019-05-09 | ACGLO | Grant (A) | +6,558 | $0 | EDGAR |
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.