ZBIO (Zenas BioPharma, Inc. Common Stock)

Insider Trading Activity

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.

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.

Form 4 Filings
50
most recent
Open-Market Buys
21
code P
Sales
0
code S
Reporting Insiders
15
current holders
ZBIO — Recent Form 4 Transactions (latest 2026-09-02)
FiledInsiderRole TypeSharesValue
2026-09-02 Christy J. Oliger Director A
2026-06-17 PATRICK G ENRIGHT Director A
2026-06-17 Lisa von Moltke See Remarks A
2026-06-17 Joseph L Farmer See Remarks A
2026-06-17 LEON O MOULDER JR See Remarks A
2026-06-17 Hongbo Lu Director A
2026-06-17 Patricia L Allen Director A
2026-06-17 JOHN J ORLOFF Director A
2026-06-17 Jennifer A. Fox See Remarks A
2026-06-17 Jason Raleigh Nunn Director A
2026-06-17 James P Boylan Director A
2026-05-18 LEON O MOULDER JR Chief Executive Officer Buy
2026-04-29 LEON O MOULDER JR Chief Executive Officer Buy
2026-04-02 Hongbo Lu Director Buy
2026-04-01 Fairmount Healthcare Fund II L.P. Director Buy
2026-02-13 Hongbo Lu Director Buy
2026-02-13 Patricia L Allen Director Buy
2026-02-03 LEON O MOULDER JR Chief Executive Officer Buy
2026-01-09 LEON O MOULDER JR Chief Executive Officer Buy
2025-10-14 PATRICK G ENRIGHT Director Buy
2025-10-14 Jason Raleigh Nunn Director Buy
2025-10-14 SR ONE CAPITAL MANAGEMENT, LLC 10%+ Owner Buy
2025-10-09 Peter Evan Harwin Director Buy
2025-10-09 LEON O MOULDER JR See Remarks Buy
2025-10-09 Hongbo Lu Director Buy
2025-06-12 Orlando Oliveira See Remarks A
2025-06-12 Joseph L Farmer See Remarks A
2025-06-12 PATRICK G ENRIGHT Director A
2025-06-12 Jennifer A. Fox See Remarks A
2025-06-12 Jason Raleigh Nunn Director A
2025-06-12 JOHN J ORLOFF Director A
2025-06-12 LEON O MOULDER JR See Remarks A
2025-06-12 Peter Evan Harwin Director A
2025-06-12 Patricia L Allen Director A
2025-06-12 James P Boylan Director A
2025-06-12 Hongbo Lu Director A
2025-04-28 Ting Xiao Director Buy
2025-04-17 Lisa von Moltke See Remarks A
2025-02-19 LEON O MOULDER JR Chief Executive Officer Buy
2025-02-11 Ting Xiao Director Buy
2024-12-18 Orlando Oliveira Chief Commercial Officer A
2024-12-18 Jennifer A. Fox See Remarks A
2024-12-04 LEON O MOULDER JR Chief Executive Officer Buy
2024-11-20 LEON O MOULDER JR Chief Executive Officer Buy
2024-09-20 LEON O MOULDER JR Chief Executive Officer Buy
2024-09-18 Wellington Biomedical Innovation Master Investors (Cayman) I L.P. 10%+ Owner C
2024-09-18 Zebra Aggregator, LP 10%+ Owner MIXED
2024-09-17 Hongbo Lu Director Buy
2024-09-17 LEON O MOULDER JR Chief Executive Officer C
2024-09-17 Fairmount Healthcare Fund II L.P. Director MIXED
ZBIO — Current Insider Holders
InsiderRole Shares HeldValue
10%+ Owner 3,761,359
Director 2,359,025
Director 2,209,025
Director 1,844,659
Director 1,173,395
10%+ Owner 1,173,395
Director 1,003,814
10%+ Owner 669,061
10%+ Owner 600,906
See Remarks 520,083
Director 426,736
Director 19,860
Director 10,000
See Remarks 1,592
See Remarks 974
How to read Form 4 activity

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.