Insider · CIK 0001372455
Brian S Posner
Files at ACGL (ARCH CAPITAL GROUP LTD.), DYN (Dyne Therapeutics, Inc.). First filing Aug 4, 2025, latest Oct 6, 2026.
Where the trades landed
Last year at the 2 companies this insider has traded most, with each buy and sell on the bar it happened.
ACGL: ARCH CAPITAL GROUP LTD.
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value. Click a marked bar to open the signal.Charts by TradingView Lightweight Charts™
DYN: Dyne Therapeutics, Inc.
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value. Click a marked bar to open the signal.Charts by TradingView Lightweight Charts™
Signals
This insider’s open-market buys and sells, scored.
| Score | Company | Value | Holdings | Price context | Filed |
|---|---|---|---|---|---|
| 32Weak | DYNbuy Dyne Therapeutics, Inc. | $40k 2,500 shares | +10% | +21% from low-43% from high | |
| 57Moderate | ARCH CAPITAL GROUP LTD. | $51k 3,000 shares | -60% | +12% from low-7% from high | |
| 35Weak | ACGLbuy ARCH CAPITAL GROUP LTD. | $17k 1,000 shares | +25% | +4% from low-19% from high |
Transactions
Every row this insider has filed, newest first.
| Date | Company | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| Oct 2, 2026 | DYN Dyne Therapeutics, Inc. | POpen-market purchase Common Stock | +2,500 | $16.00 | $40k | 27,000 | 6 d ago |
| Mar 11, 2026 | ACGL ARCH CAPITAL GROUP LTD. | SOpen-market sale Depositary Shares, Series G | -3,000 | $17.12 | $51k | 2,000 | Mar 12, 2026 |
| Oct 1, 2025 | DYN Dyne Therapeutics, Inc. | AGrant or award Stock option (right to buy)derivative | +70,000 | $0.00 | $0 | 70,000 | Oct 2, 2025 |
| Aug 1, 2025 | ACGL ARCH CAPITAL GROUP LTD. | POpen-market purchase Depositary Shares, Series G | +1,000 | $17.34 | $17k | 5,000 | Aug 4, 2025 |
| May 7, 2025 | ACGL ARCH CAPITAL GROUP LTD. | AGrant or award Common Shares, $.0011 par value per share | +1,564 | - | - | 120,104 | May 9, 2025 |
Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.