Posner Brian S
SEC Form 4 insider trading activity
Posner Brian S has filed 12 SEC Form 4 filings (12 transaction rows) across 2 companies, including DYN, ACGL, with disclosures dating back to 2026. 12 of those filings fall inside the rolling window. Most recent filing: Oct 6, 2026.
On the most recent filing, Posner Brian S is listed as Director at Dyne Therapeutics, Inc. Inside the rolling window, Posner Brian S reported 8 open-market purchases totaling $315K in DYN and 3 open-market sales totaling $145K in ACGL. The largest disclosed transaction in the window is a sale of 3,000 ACGL shares on Jun 3, 2026, worth $59K.
Companies traded
Other insiders at DYN
Insider Buying
$315K
reported purchases (SEC code P)
Insider Selling
$145K
reported sales (SEC code S)
Companies
2
in the rolling window
| Source | |||||||
|---|---|---|---|---|---|---|---|
| DYN | Director | Purchase | 2,500 | $40K | Oct 6 | SEC ↗ | |
| DYN | Director | Purchase | 2,000 | $34K | Jun 9 | SEC ↗ | |
| DYN | Director | Purchase | 2,500 | $44K | Jun 5 | SEC ↗ | |
| ACGL | Director | Sale | 3,000 | $59K | Jun 4 | SEC ↗ | |
| DYN | Director | Purchase | 2,000 | $36K | May 28 | SEC ↗ | |
| DYN | Director | Purchase | 2,500 | $43K | May 22 | SEC ↗ | |
| ACGL | Director | Sale | 2,000 | $34K | May 12 | SEC ↗ | |
| DYN | Director | Purchase | 2,000 | $34K | Apr 1 | SEC ↗ | |
| DYN | Director | Purchase | 2,000 | $39K | Mar 13 | SEC ↗ | |
| ACGL | Director | Sale | 3,000 | $51K | Mar 12 | SEC ↗ | |
| DYN | Director | Purchase | 3,000 | $45K | Mar 10 | SEC ↗ |
Frequently asked questions
How many SEC Form 4 filings has Posner Brian S made?
Posner Brian S has filed 12 SEC Form 4 filings (12 transaction rows) across 2 companies, including DYN, ACGL since 2026.
Which companies does Posner Brian S trade?
Posner Brian S has filed SEC Form 4 disclosures for 2 companies, including DYN, ACGL.
When was Posner Brian S's most recent SEC Form 4 filing?
Posner Brian S's most recent SEC Form 4 filing on Tracefour is dated Oct 6, 2026.
What is Posner Brian S's total buy and sell value in the current window?
Inside the rolling retention window, Posner Brian S bought $315K and sold $145K based on SEC Form 4 filings.
What was Posner Brian S's largest disclosed transaction?
The largest disclosed transaction in the current window is a sale of 3,000 ACGL shares on 2026-06-03, worth $59K, per SEC Form 4 filings.