ZBIO · Insider Trading
Zenas BioPharma, Inc. Common Stock
Every open-market purchase and sale reported by ZBIO officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-09-02 | Christy J. Oliger | Director | A | +37,000 deriv. | — |
| 2026-06-17 | Patrick G Enright | Director | A | +18,500 deriv. | — |
| 2026-06-17 | Lisa von Moltke | See Remarks | A | +150,000 deriv. | — |
| 2026-06-17 | Joseph L Farmer | See Remarks | A | +974 | +$13.00K |
| 2026-06-17 | Leon O Moulder Jr | See Remarks | A | +500,000 deriv. | — |
| 2026-06-17 | Hongbo Lu | Director | A | +18,500 deriv. | — |
| 2026-06-17 | Patricia L Allen | Director | A | +18,500 deriv. | — |
| 2026-06-17 | John J Orloff | Director | A | +18,500 deriv. | — |
| 2026-06-17 | Jennifer A. Fox | See Remarks | A | +1,592 | +$21.25K |
| 2026-06-17 | Jason Raleigh Nunn | Director | A | +18,500 deriv. | — |
| 2026-06-17 | James P Boylan | Director | A | +18,500 deriv. | — |
| 2026-05-18 | Leon O Moulder Jr | Chief Executive Officer | Buy | +60,000 | +$1.01M |
| 2026-04-29 | Leon O Moulder Jr | Chief Executive Officer | Buy | +60,000 | +$1.07M |
| 2026-04-02 | Hongbo Lu | Director | Buy | +3,768 | +$70.20K |
| 2026-04-01 | Fairmount Healthcare Fund II L.P. | Director | Buy | +600,000 | +$12.00M |
| 2026-02-13 | Hongbo Lu | Director | Buy | +25,985 | +$584.66K |
| 2026-02-13 | Patricia L Allen | Director | Buy | +19,860 | +$499.75K |
| 2026-02-03 | Leon O Moulder Jr | Chief Executive Officer | Buy | +57,000 | +$1.02M |
| 2026-01-09 | Leon O Moulder Jr | Chief Executive Officer | Buy | +100,000 | +$1.64M |
| 2025-10-14 | Patrick G Enright | Director | Buy | +117,255 | +$2.25M |
| 2025-10-14 | Jason Raleigh Nunn | Director | Buy | +63,158 | +$1.20M |
| 2025-10-14 | SR ONE CAPITAL MANAGEMENT, LLC | 10%+ Owner | Buy | +252,630 | +$4.80M |
| 2025-10-09 | Peter Evan Harwin | Director | Buy | +1,264,876 | +$24.03M |
| 2025-10-09 | Leon O Moulder Jr | See Remarks | Buy | +36,928 | +$769.95K |
| 2025-10-09 | Hongbo Lu | Director | Buy | +321,983 | +$6.00M |
| 2025-06-12 | Orlando Oliveira | See Remarks | A | +100,000 deriv. | — |
| 2025-06-12 | Joseph L Farmer | See Remarks | A | +175,000 deriv. | — |
| 2025-06-12 | Patrick G Enright | Director | A | +18,500 deriv. | — |
| 2025-06-12 | Jennifer A. Fox | See Remarks | A | +150,000 deriv. | — |
| 2025-06-12 | Jason Raleigh Nunn | Director | A | +18,500 deriv. | — |
| 2025-06-12 | John J Orloff | Director | A | +18,500 deriv. | — |
| 2025-06-12 | Leon O Moulder Jr | See Remarks | A | +400,000 deriv. | — |
| 2025-06-12 | Peter Evan Harwin | Director | A | +74,000 deriv. | — |
| 2025-06-12 | Patricia L Allen | Director | A | +18,500 deriv. | — |
| 2025-06-12 | James P Boylan | Director | A | +18,500 deriv. | — |
| 2025-06-12 | Hongbo Lu | Director | A | +18,500 deriv. | — |
| 2025-04-28 | Ting Xiao | Director | Buy | +10,000 | +$77.60K |
| 2025-04-17 | Lisa von Moltke | See Remarks | A | +400,000 deriv. | — |
| 2025-02-19 | Leon O Moulder Jr | Chief Executive Officer | Buy | +25,000 | +$166.75K |
| 2025-02-11 | Ting Xiao | Director | Buy | +10,000 | +$77.60K |
| 2024-12-18 | Orlando Oliveira | Chief Commercial Officer | A | +7,775 deriv. | — |
| 2024-12-18 | Jennifer A. Fox | See Remarks | A | +8,125 deriv. | — |
| 2024-12-04 | Leon O Moulder Jr | Chief Executive Officer | Buy | +70,000 | +$718.10K |
| 2024-11-20 | Leon O Moulder Jr | Chief Executive Officer | Buy | +10,000 | +$148.93K |
| 2024-09-20 | Leon O Moulder Jr | Chief Executive Officer | Buy | +20,000 | +$360.82K |
| 2024-09-18 | Wellington Biomedical Innovation Master Investors (Cayman) I L.P. | 10%+ Owner | C | +801,624 | — |
| 2024-09-18 | Zebra Aggregator, LP | 10%+ Owner | MIXED | +7,522,718 | +$30.00M |
| 2024-09-17 | Hongbo Lu | Director | Buy | +58,823 | +$999.99K |
| 2024-09-17 | Leon O Moulder Jr | Chief Executive Officer | C | +693,175 | — |
| 2024-09-17 | Fairmount Healthcare Fund II L.P. | Director | MIXED | +6,419,564 | +$20.40M |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| Fairmount Healthcare Fund II L.P. | Director | 2,359,025 | $64.26M |
| Peter Evan Harwin | Director | 2,209,025 | $60.17M |
| Patrick G Enright | Director | 1,844,659 | $50.25M |
| Jason Raleigh Nunn | Director | 1,173,395 | $31.96M |
| SR ONE CAPITAL MANAGEMENT, LLC | 10%+ Owner | 1,173,395 | $31.96M |
| Leon O Moulder Jr | See Remarks | 520,083 | $14.17M |
| Hongbo Lu | Director | 426,736 | $11.62M |
| Patricia L Allen | Director | 19,860 | $540.99K |
| Ting Xiao | Director | 10,000 | $272.40K |
| Jennifer A. Fox | See Remarks | 1,592 | $43.37K |
| Joseph L Farmer | See Remarks | 974 | $26.53K |
Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.
Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.
Full filing history and per-insider positions are on the ZBIO quote page; the site-wide leaderboard is on the insider transactions hub.
Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.