ZBIO insider buying – Zenas BioPharma, Inc.
27 insider purchases since 2016 worth $113.1M by 10 different insiders. Last 12 months: 10 purchases, $11.4M. Most recent filing: 2026-05-18.
Same time range as the chart above - each mark sits under the week of the trade. Circles = purchases (height = price paid, size = amount), red triangles = open-market sales of $50k+. Prices as reported, not adjusted for later stock splits.
Purchases are open-market buys (SEC Form 4, code "P") - insiders paying with their own money. Sales are open-market sales (code "S") of $50,000 or more; many sales are pre-planned (Rule 10b5-1) or made for taxes and diversification. Each row links to the original filing.
Bought, sold, still holding?
| Insider | Bought | First / last buy | Sold since 2016 | Holds now* | Status |
|---|---|---|---|---|---|
| SR ONE CAPITAL MANAGEMENT, LLC 10% Owner | $40.4M 2× · 2,361,609 sh | 2024-09-16 2025-10-09 | – | 5,037,854 shares as of 2025-10-14 | Holds - never sold |
| Nunn Jason Raleigh Director | $16.2M 2× · 945,510 sh | 2024-09-16 2025-10-09 | – | 3,119,959 shares as of 2025-10-14 | Holds - never sold |
| Zebra Aggregator, LP 10% Owner | $15.0M 1× · 882,353 sh | 2024-09-16 2024-09-16 | – | 3,761,359 shares as of 2024-09-18 | Holds - never sold |
| Harwin Peter Evan Director | $11.1M 2× · 616,219 sh | 2024-09-16 2025-10-07 | – | 2,209,025 shares as of 2025-10-09 | Holds - never sold |
| ENRIGHT PATRICK G Director | $9.7M 2× · 557,255 sh | 2024-09-16 2025-10-09 | – | 1,844,659 shares as of 2025-10-14 | Holds - never sold |
| Lu Hongbo Director | $9.2M 5× · 485,559 sh | 2024-09-13 2026-03-31 | – | 426,736 shares as of 2026-04-02 | Holds - never sold |
| MOULDER LEON O JR CEO | $7.9M 10× · 492,928 sh | 2024-09-18 2026-05-18 | – | 520,083 shares as of 2026-05-18 | Holds - never sold |
| Kiselak Tomas Director | $3.0M 1× · 150,000 sh | 2026-03-31 2026-03-31 | – | 2,359,025 shares as of 2026-04-01 | Holds - never sold |
| Allen Patricia L Director | $499,746 1× · 19,860 sh | 2026-02-12 2026-02-12 | – | 15,700 shares as of 2026-02-13 | Holds - never sold |
| Xiao Ting Director | $77,600 1× · 10,000 sh | 2025-02-07 2025-02-07 | – | 10,000 shares as of 2025-04-28 | Holds - never sold |
* Shares held after the insider's most recent SEC filing for this company (all share classes, direct and indirect). If an insider stops filing, later changes are not known.
Insider buying and selling by year
| Year | Purchases | Bought | Buyers | Sales | Sold |
|---|---|---|---|---|---|
| 2026 | 10 | $11.4M | 4 | – | – |
| 2025 | 8 | $18.9M | 7 | – | – |
| 2024 | 9 | $82.8M | 7 | – | – |
Insider purchases
| Filed | Insider | Role | Shares | Avg price | Value | Holdings | Filing |
|---|---|---|---|---|---|---|---|
| 2026-05-18 | MOULDER LEON O JR | CEO | 60,000 | $16.88 | $1.0M | +162.5% | SEC |
| 2026-04-29 | MOULDER LEON O JR | CEO | 60,000 | $17.79 | $1.1M | +3.5% | SEC |
| 2026-04-02 | Lu Hongbo | Director | 3,768 | $18.63 | $70,198 | +0.9% | SEC |
| 2026-04-01 | Kiselak Tomas | Director | 150,000 | $20.00 | $3.0M | +6.8% | SEC |
| 2026-03-31 | Lu Hongbo | Director | 75,000 | $20.00 | $1.5M | +21.6% | SEC |
| 2026-03-31 | MOULDER LEON O JR | CEO | 54,000 | $18.91 | $1.0M | +3.2% | SEC |
| 2026-02-13 | Allen Patricia L | Director | 19,860 | $25.16 | $499,746 | SEC | |
| 2026-02-13 | Lu Hongbo | Director | 25,985 | $22.50 | $584,662 | +8.1% | SEC |
| 2026-02-03 | MOULDER LEON O JR | CEO | 57,000 | $17.96 | $1.0M | +15.6% | SEC |
| 2026-01-09 | MOULDER LEON O JR | CEO | 100,000 | $16.39 | $1.6M | +37.6% | SEC |
| 2025-10-14 | SR ONE CAPITAL MANAGEMENT, LLC | 10% Owner | 126,315 | $19.00 | $2.4M | +7.1% | SEC |
| 2025-10-14 | Nunn Jason Raleigh | Director | 63,158 | $19.00 | $1.2M | +5.7% | SEC |
| 2025-10-14 | ENRIGHT PATRICK G | Director | 117,255 | $19.19 | $2.3M | +6.8% | SEC |
| 2025-10-09 | MOULDER LEON O JR | Officer | 36,928 | $20.85 | $769,949 | SEC | |
| 2025-10-09 | Harwin Peter Evan | Director | 316,219 | $19.00 | $6.0M | +16.7% | SEC |
| 2025-10-09 | Lu Hongbo | Director | 321,983 | $18.63 | $6.0M | SEC | |
| 2025-02-19 | MOULDER LEON O JR | CEO | 25,000 | $6.67 | $166,750 | +10.4% | SEC |
| 2025-02-11 | Xiao Ting | Director | 10,000 | $7.76 | $77,600 | +27.0% | SEC |
| 2024-12-04 | MOULDER LEON O JR | CEO | 70,000 | $10.26 | $718,100 | +40.9% | SEC |
| 2024-11-20 | MOULDER LEON O JR | CEO | 10,000 | $14.89 | $148,925 | +6.2% | SEC |
| 2024-09-20 | MOULDER LEON O JR | CEO | 20,000 | $18.04 | $360,820 | +1.2% | SEC |
| 2024-09-18 | Zebra Aggregator, LP | 10% Owner | 882,353 | $17.00 | $15.0M | +30.6% | SEC |
| 2024-09-17 | Lu Hongbo | Director | 58,823 | $17.00 | $999,991 | SEC | |
| 2024-09-16 | SR ONE CAPITAL MANAGEMENT, LLC | 10% Owner | 2,235,294 | $17.00 | $38.0M | SEC | |
| 2024-09-16 | Nunn Jason Raleigh | Director | 882,352 | $17.00 | $15.0M | +82.9% | SEC |
| 2024-09-16 | Harwin Peter Evan | Director | 300,000 | $17.00 | $5.1M | +23.0% | SEC |
| 2024-09-16 | ENRIGHT PATRICK G | Director | 440,000 | $17.00 | $7.5M | +131.5% | SEC |
Compiled automatically from public SEC filings. Not investment advice. Get every new insider purchase in the daily report.
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