Insider · CIK 0001586226
Arthur Tzianabos
Files at STOK (Stoke Therapeutics, Inc.), QTTB (Q32 Bio Inc.). First filing Feb 15, 2024, latest Mar 12, 2026.
In brief
Arthur Tzianabos files SEC Form 4 as director and chair at STOK (Stoke Therapeutics, Inc.), and also at QTTB (Q32 Bio Inc.). Since Feb 15, 2024, Arthur Tzianabos has reported 0 open-market buys worth $0 and 2 open-market sells worth $182k, the latest filed on Mar 12, 2026.
A track record needs three past buys with six months of prices behind them; Arthur Tzianabos has 0, so none is measured yet.
The newest scored trade: sold $174k of STOK on Mar 10, 2026, filed Mar 12, 2026, scored 16 (weak), under a 10b5-1 plan. In the last 12 months: 0 buys worth $0 and 1 sell worth $174k.
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.
STOK: Stoke 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™
QTTB: Q32 Bio 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 |
|---|---|---|---|---|---|
| 16Weak | Stoke Therapeutics, Inc. | $174k 4,355 shares | -12% | +550% from low0% from high | |
| 0Weak | Q32 Bio Inc. | $7,445 13,037 shares | -9% | +24% from low-61% from high |
Planned sales
Form 144 notices this insider filed before selling restricted or control stock, newest first.
| Filed | Company | Shares | Value | Sale date | Past 3 months |
|---|---|---|---|---|---|
| Mar 10, 2026 | STOK STOKE THERAPEUTICS INC | 90,508 0.16% of outstanding | $3.5M | Mar 10, 2026 | none |
Transactions
Every row this insider has filed, 15 in all, newest first.
| Date | Company | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| Jun 12, 2026 | QTTB Q32 Bio Inc. | AGrant or award Stock Option (Right to Buy)derivative | +10,826 | $0.00 | $0 | 10,826 | Jul 21, 2026 |
| Jun 12, 2026 | QTTB Q32 Bio Inc. | AGrant or award Stock Option (Right to Buy)derivative | +9,810 | $0.00 | $0 | 9,810 | Jun 16, 2026 |
| Jun 3, 2026 | STOK Stoke Therapeutics, Inc. | AGrant or award Director Stock Option (Right to Buy)derivative | +17,786 | $0.00 | $0 | 17,786 | Jun 5, 2026 |
| Mar 10, 2026 | STOK Stoke Therapeutics, Inc. | MOption exercise Common Stock10b5-1 | +3,955 | $8.33 | $33k | 35,694 | Mar 12, 2026 |
| Mar 10, 2026 | STOK Stoke Therapeutics, Inc. | SOpen-market sale Common Stock10b5-1 | -4,355 | $40.00 | $174k | 31,339 | Mar 12, 2026 |
| Mar 10, 2026 | STOK Stoke Therapeutics, Inc. | MOption exercise Stock Option (Right to Buy)derivative10b5-1 | -3,955 | $0.00 | $0 | 118,696 | Mar 12, 2026 |
| Oct 23, 2025 | QTTB Q32 Bio Inc. | AGrant or award Stock Option (Right to Buy)derivative | +53,521 | $0.00 | $0 | 53,521 | Oct 27, 2025 |
| Mar 25, 2024 | QTTB Q32 Bio Inc. | AGrant or award Stock Option (Right to Buy)derivative | +12,767 | $0.00 | $0 | 12,767 | Mar 27, 2024 |
| Feb 13, 2024 | STOK Stoke Therapeutics, Inc. | MOption exercise Common Stock | +31,739 | $2.19 | $70k | 31,739 | Feb 15, 2024 |
| Jan 1, 2024 | QTTB Q32 Bio Inc. | MOption exercise Common Stock10b5-1 | +14,280 | - | - | 122,675 | Feb 15, 2024 |
| Feb 13, 2024 | STOK Stoke Therapeutics, Inc. | MOption exercise Stock Option (Right to Buy)derivative | -31,739 | $0.00 | $0 | 0 | Feb 15, 2024 |
| Jan 1, 2024 | QTTB Q32 Bio Inc. | MOption exercise Common Stock10b5-1 | +19,140 | - | - | 141,815 | Feb 15, 2024 |
| Jan 9, 2024 | QTTB Q32 Bio Inc. | SOpen-market sale Common Stock10b5-1 | -13,037 | $0.57 | $7,445 | 128,778 | Feb 15, 2024 |
| Jan 1, 2024 | QTTB Q32 Bio Inc. | MOption exercise Restricted Stock Unitsderivative10b5-1 | -14,280 | $0.00 | $0 | 0 | Feb 15, 2024 |
| Jan 1, 2024 | QTTB Q32 Bio Inc. | MOption exercise Restricted Stock Unitsderivative10b5-1 | -19,140 | $0.00 | $0 | 19,720 | Feb 15, 2024 |
Questions about Arthur Tzianabos
Answered from the filings on this page, as of the latest one.
Is Arthur Tzianabos buying or selling?
In the last 12 months Arthur Tzianabos reported 0 open-market buys worth $0 and 1 open-market sell worth $174k on SEC Form 4; the latest was sold $174k of STOK on Mar 10, 2026. Grants, option exercises and tax withholding are not counted.
How did Arthur Tzianabos's past buys perform?
Not measured yet. InsiderTell needs three past buys with six months of prices to publish a track record, and Arthur Tzianabos has 0.
Where does Arthur Tzianabos file Form 4?
Arthur Tzianabos has filed Form 4 at STOK (Stoke Therapeutics, Inc.) as Interim Executive Chair; QTTB (Q32 Bio 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.