Mersana Therapeutics, Inc. (MRSN) is a publicly traded company in the Unknown sector. Across all available filings, 30 corporate insiders have executed 375 transactions totaling $231.6M, demonstrating a bullish sentiment with $222.1M in net insider flow. The most recent transaction on Oct 27, 2025 involved a sale of 77 shares valued at $762.
No significant insider buying has been recorded for MRSN in the recent period.
No significant insider selling has been recorded for MRSN in the recent period.
Based on recent SEC filings, insider sentiment for MRSN is bullish with an Insider Alignment Score of 98/100 and a net flow of $222.1M. Insiders are accumulating shares, which historically signals confidence in the company's future performance.
Insider trading at Mersana Therapeutics, Inc. (MRSN) refers to stock transactions made by corporate insiders—executives, directors, and beneficial owners holding more than 10% of the company's shares. These individuals have access to material non-public information and are required by law to report their trades to the SEC within two business days. Currently, 30 insiders are actively trading MRSN stock, having executed 375 transactions in the past 90 days. The most active insider is Andrew A. F. Hack (Executive), who has made 19 transactions totaling $43.8M.
Get notified when executives and directors at MRSN file new Form 4 transactions
Date | Insider | Title | Type | Shares | Price | Value | Flags |
|---|---|---|---|---|---|---|---|
| Oct 27, 2025 | Bala Mohan | Executive | Sale | 77 | $9.90 | $762 | |
| Oct 25, 2025 | Bala Mohan | Executive | Option Exercise | 250 | $N/A | $0 | |
| Sep 12, 2025 | H. Huber Martin Jr | Executive | Sale | 2,012 | $7.31 | $14.7K | |
| Sep 11, 2025 | H. Huber Martin Jr | Executive | Option Exercise | 6,670 | $N/A | $0 | |
| Sep 12, 2024 | H. Huber Martin Jr | Executive | Sale | 50,423 | $1.76 | $88.7K | 10b5-1 |
| Sep 11, 2024 | H. Huber Martin Jr | Executive | Option Exercise | 166,750 | $N/A | $0 | 10b5-1 |
| Jan 16, 2024 | Bala Mohan | Executive | Sale | 3,431 | $2.71 | $9.3K | 10b5-1 |
| Jan 16, 2024 | Deschuytner Brian | Executive | Sale | 9,327 | $2.71 | $25.3K | 10b5-1 |
| Jan 16, 2024 | Carvajal Alejandra | Executive | Sale | 4,381 | $2.71 | $11.9K | 10b5-1 |
| Jan 16, 2024 | B. Lowinger Timothy | Executive | Sale | 10,409 | $2.71 | $28.2K | 10b5-1 |
| Jan 16, 2024 | Mandelia Ashish | Executive | Sale | 5,025 | $2.71 | $13.6K | 10b5-1 |
| Jan 16, 2024 | Misra Tushar | Executive | Sale | 3,357 | $2.71 | $9.1K | 10b5-1 |
| Jan 16, 2024 | Protopapas Anna | Executive | Sale | 29,399 | $2.71 | $79.7K | 10b5-1 |
| Jan 15, 2024 | Deschuytner Brian | Executive | Option Exercise | 6,250 | $N/A | $0 | 10b5-1 |
| Jan 15, 2024 | Deschuytner Brian | Executive | Option Exercise | 3,958 | $N/A | $0 | 10b5-1 |
| TYPE | COUNT | VALUE | % |
|---|---|---|---|
Purchase(P) | 35 | $226.8M | 97.5% |
Sale(S) | 84 | $4.8M | 2.1% |
Exercise(M) | 110 | $750.9K | 0.3% |
Payment(F) | 5 | $230.5K | 0.1% |
Exercise (Options)(X) | 1 | $3.5K | 0.0% |
Award(A) | 16 | $0 | 0.0% |
Gift(G) | 3 | $0 | 0.0% |
Other(J) | 108 | $0 | 0.0% |
Conversion(C) | 13 | $0 | 0.0% |
Insiders at Mersana Therapeutics, Inc. are accumulating shares at an accelerated pace. With 30 insiders making 375 transactions totaling $226.8M in purchases versus $4.8M in sales, the net buying activity of $222.1M signals strong executive confidence. Andrew A. F. Hack (Executive) leads the buying activity with $43.8M in transactions across all time.