John M. Dineen serves as Executive at MERRIMACK PHARMACEUTICALS INC, where they oversee executive responsibilities. Since joining the company, John M. Dineen has executed 14 insider transactions totaling $1.5M, demonstrating a bullish approach to their equity position. Their most recent transaction on Nov 7, 2025 involved receiving (via award) 1,635 shares valued at $0.
John M. Dineen currently holds 9,135 shares of MERRIMACK PHARMACEUTICALS INC (MACK), valued at approximately $0. This represents their equity stake as Executive.
Based on SEC Form 4 filings, John M. Dineen has been a net buyer of MACK stock. They have purchased $1.5M and sold $0 worth of shares.
John M. Dineen's most recent insider trade was on Nov 7, 2025, when they sold 1,635 shares at $0.00 per share.
Get notified when new Form 4 filings are submitted
| $59.52 |
| Discretionary |
| Nov 10, 2023 | LRCX | $0 | Award | 86 | $N/A | Discretionary |
| Nov 10, 2023 | LRCX | $0 | Award | 369 | $N/A | Discretionary |
| Sep 28, 2023 | SYNH | $0 | Disposition | 4,863 | $N/A | Discretionary |
| Sep 28, 2023 | SYNH | $973.0K | Disposition | 22,629 | $43.00 | Discretionary |
| May 25, 2023 | SYNH | $0 | Award | 4,863 | $N/A | Discretionary |
| May 25, 2022 | SYNH | $0 | Award | 2,839 | $N/A | Discretionary |
| May 12, 2021 | SYNH | $0 | Award | 2,364 | $N/A | Discretionary |
| Jul 6, 2020 | SYNH | $513.7K | Purchase | 8,691 | $59.11 | Discretionary |
| May 27, 2020 | SYNH | $175.0K | Award | 2,803 | $62.43 | Discretionary |
| May 24, 2019 | SYNH | $175.0K | Award | 4,122 | $42.45 | Discretionary |
| Dec 10, 2018 | SYNH | $0 | Award | 1,630 | $N/A | Discretionary |
| Aug 12, 2015 | MACK | $1.0M | Purchase | 100,000 | $10.15 | Discretionary |