Insider · CIK 0001653276
Martin H. Huber Jr.
Files at SNDX (Syndax Pharmaceuticals Inc), MRSN (Mersana Therapeutics, Inc.), ACTU (ACTUATE THERAPEUTICS, INC.). First filing Jan 17, 2025, latest Sep 15, 2025.
In brief
Martin H. Huber Jr. files SEC Form 4 as CEO, president and director at MRSN (Mersana Therapeutics, Inc.), and also at SNDX (Syndax Pharmaceuticals Inc), ACTU (ACTUATE THERAPEUTICS, INC.). Since Jan 17, 2025, Martin H. Huber Jr. has reported 1 open-market buy worth $45k and 2 open-market sells worth $17k, the latest filed on Sep 15, 2025.
A track record needs three past buys with six months of prices behind them; Martin H. Huber Jr. has 0, so none is measured yet.
The newest scored trade: sold $15k of MRSN on Sep 12, 2025, filed Sep 15, 2025, scored 0 (weak), under a 10b5-1 plan.
Where the trades landed
Last year at the company this insider has traded most, with each buy and sell on the bar it happened.
SNDX: Syndax Pharmaceuticals 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 |
|---|---|---|---|---|---|
| 0Weak | Mersana Therapeutics, Inc. | $15k 2,012 shares | -17% | - | |
| 57Moderate | Syndax Pharmaceuticals Inc | $45k 5,000 shares | +7% | +4% from low-57% from high | |
| 5Weak | Mersana Therapeutics, Inc. | $2,618 4,514 shares | -4% | - |
Transactions
Every row this insider has filed, 31 in all, newest first.
| Date | Company | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| May 21, 2026 | ACTU ACTUATE THERAPEUTICS, INC. | AGrant or award Stock Optionsderivative | +15,000 | $0.00 | $0 | 15,000 | May 22, 2026 |
| Feb 4, 2026 | SNDX Syndax Pharmaceuticals Inc | AGrant or award Common Stock | +24,000 | $0.00 | $0 | 103,000 | Feb 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | UTender of shares Common Stock | -9,573 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -5,938 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -26,713 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -1,923 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -99 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -1,002 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -407 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -1,800 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -135 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -734 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -179 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -12,121 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -27,878 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -364 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -497 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Stock Option (right to buy)derivative | -7,467 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Restricted Stock Unitsderivative | -13,340 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Restricted Stock Unitsderivative | -1,328 | - | - | 0 | Jan 6, 2026 |
| Jan 6, 2026 | MRSN Mersana Therapeutics, Inc. | DDisposition to issuer Restricted Stock Unitsderivative | -7,256 | - | - | 0 | Jan 6, 2026 |
| Sep 11, 2025 | MRSN Mersana Therapeutics, Inc. | MOption exercise Common Stock10b5-1 | +6,670 | $0.00 | $0 | 11,584 | Sep 15, 2025 |
| Sep 12, 2025 | MRSN Mersana Therapeutics, Inc. | SOpen-market sale Common Stock10b5-1 | -2,012 | $7.31 | $15k | 9,572 | Sep 15, 2025 |
| Sep 11, 2025 | MRSN Mersana Therapeutics, Inc. | MOption exercise Restricted Stock Unitderivative10b5-1 | -6,670 | $0.00 | $0 | 13,340 | Sep 15, 2025 |
| May 19, 2025 | SNDX Syndax Pharmaceuticals Inc | POpen-market purchase Common Stock | +5,000 | $8.99 | $45k | 79,000 | May 19, 2025 |
| Feb 5, 2025 | SNDX Syndax Pharmaceuticals Inc | AGrant or award Common Stock | +25,000 | $0.00 | $0 | 74,000 | Feb 7, 2025 |
| Jan 15, 2025 | MRSN Mersana Therapeutics, Inc. | MOption exercise Common Stock10b5-1 | +11,062 | $0.00 | $0 | 127,389 | Jan 17, 2025 |
| Jan 16, 2025 | MRSN Mersana Therapeutics, Inc. | SOpen-market sale Common Stock10b5-1 | -4,514 | $0.58 | $2,618 | 122,875 | Jan 17, 2025 |
| Jan 15, 2025 | MRSN Mersana Therapeutics, Inc. | MOption exercise Restricted Stock Unitderivative10b5-1 | -11,062 | $0.00 | $0 | 33,188 | Jan 17, 2025 |
| Jan 15, 2025 | MRSN Mersana Therapeutics, Inc. | AGrant or award Stock Option (Right to Buy)derivative10b5-1 | +816,300 | $0.00 | $0 | 816,300 | Jan 17, 2025 |
| Jan 15, 2025 | MRSN Mersana Therapeutics, Inc. | AGrant or award Restricted Stock Unitderivative10b5-1 | +181,400 | $0.00 | $0 | 181,400 | Jan 17, 2025 |
Questions about Martin H. Huber Jr.
Answered from the filings on this page, as of the latest one.
Is Martin H. Huber Jr. buying or selling?
Not in the last 12 months. Martin H. Huber Jr.'s latest open-market trade on SEC Form 4 was sold $15k of MRSN on Sep 12, 2025.
How did Martin H. Huber Jr.'s past buys perform?
Not measured yet. InsiderTell needs three past buys with six months of prices to publish a track record, and Martin H. Huber Jr. has 0.
Where does Martin H. Huber Jr. file Form 4?
Martin H. Huber Jr. has filed Form 4 at MRSN (Mersana Therapeutics, Inc.) as President, CEO; SNDX (Syndax Pharmaceuticals Inc); ACTU (ACTUATE THERAPEUTICS, INC.). A Form 4 is required of officers, directors and holders of more than 10% of a share class within two business days of a trade.
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.