ETNB · Insider Trading
89bio, Inc. Common Stock
Every open-market purchase and sale reported by ETNB 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 |
|---|---|---|---|---|---|
| 2025-10-30 | Edward Morrow Atkinson III | Director | D | −148,950 deriv. | — |
| 2025-10-30 | Martin Babler | Director | D | −124,100 deriv. | — |
| 2025-10-30 | Quoc Le-Nguyen | See Remarks | MIXED | −315,378 | — |
| 2025-10-30 | Steven Altschuler | Director | D | −213,450 deriv. | — |
| 2025-10-30 | Charles McWherter | Director | U | −25,000 | — |
| 2025-10-30 | Michael R Hayden | Director | U | −246,420 | — |
| 2025-10-30 | Francis Willard Sarena | Chief Operating Officer | U | −75,310 | — |
| 2025-10-30 | Derek DiRocco | Director | D | −180,450 deriv. | — |
| 2025-10-30 | Rohan Palekar | Chief Executive Officer | MIXED | −809,273 | — |
| 2025-10-30 | Harry H Mansbach | Chief Medical Officer | MIXED | −302,656 | — |
| 2025-10-30 | Ryan Martins | Chief Financial Officer | MIXED | −339,295 | — |
| 2025-10-30 | Lota S. Zoth | Director | D | −186,450 deriv. | — |
| 2025-10-30 | Kathleen Laporte | Director | D | −166,450 deriv. | — |
| 2025-10-23 | Ryan Martins | Chief Financial Officer | M | +80,799 | +$256.47K |
| 2025-08-05 | Quoc Le-Nguyen | See Remarks | F | −8,202 | −$75.13K |
| 2025-08-05 | Ryan Martins | Chief Financial Officer | F | −7,680 | −$70.35K |
| 2025-08-05 | Harry H Mansbach | Chief Medical Officer | F | −7,680 | −$70.35K |
| 2025-08-05 | Francis Willard Sarena | Chief Operating Officer | F | −6,185 | −$58.23K |
| 2025-08-05 | Rohan Palekar | Chief Executive Officer | F | −55,836 | −$511.46K |
| 2025-07-17 | Quoc Le-Nguyen | See Remarks | Sell | −10,461 | −$115.28K |
| 2025-06-13 | Ryan Martins | Chief Financial Officer | F | −8,498 | −$81.75K |
| 2025-06-13 | Harry H Mansbach | Chief Medical Officer | F | −8,498 | −$81.75K |
| 2025-06-13 | Quoc Le-Nguyen | See Remarks | F | −9,032 | −$86.89K |
| 2025-04-17 | Quoc Le-Nguyen | See Remarks | Sell | −15,329 | −$91.21K |
| 2025-02-19 | Ryan Martins | Chief Financial Officer | F | −780 | −$8.24K |
| 2025-02-19 | Rohan Palekar | Chief Executive Officer | F | −3,249 | −$34.34K |
| 2025-02-19 | Harry H Mansbach | Chief Medical Officer | F | −1,050 | −$11.10K |
| 2025-02-19 | Quoc Le-Nguyen | See Remarks | MIXED | +13,700 | +$72.90K |
| 2025-02-11 | Harry H Mansbach | Chief Medical Officer | F | −3,817 | −$43.55K |
| 2025-02-11 | Ryan Martins | Chief Financial Officer | F | −3,828 | −$43.68K |
| 2025-02-11 | Quoc Le-Nguyen | See Remarks | F | −3,793 | −$43.28K |
| 2025-02-11 | Rohan Palekar | Chief Executive Officer | F | −8,946 | −$102.07K |
| 2025-02-05 | Martin Babler | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Michael R Hayden | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Steven Altschuler | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Edward Morrow Atkinson III | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Kathleen Laporte | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Charles McWherter | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Derek DiRocco | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Lota S. Zoth | Director | A | +56,400 deriv. | — |
| 2025-02-05 | Peter Kolchinsky | Director | A | +282,000 deriv. | — |
| 2025-02-04 | Quoc Le-Nguyen | See Remarks | MIXED | +76,662 | −$32.04K |
| 2025-02-04 | Harry H Mansbach | Chief Medical Officer | MIXED | +76,662 | −$32.04K |
| 2025-02-04 | Francis Willard Sarena | Chief Operating Officer | A | +53,750 | — |
| 2025-02-04 | Ryan Martins | Chief Financial Officer | MIXED | +76,662 | −$32.04K |
| 2025-02-04 | Rohan Palekar | Chief Executive Officer | MIXED | +402,402 | −$92.14K |
| 2025-02-03 | RA Capital Nexus Fund, L.P. | Director | Buy | +28,571,425 | +$250.00M |
| 2025-01-23 | Charles McWherter | Director | Buy | +15,000 | +$99.85K |
| 2025-01-17 | Quoc Le-Nguyen | See Remarks | Sell | −10,963 | −$71.15K |
| 2024-12-16 | Quoc Le-Nguyen | See Remarks | A | −95,000 | — |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| Rajeev M. Shah | Director | 4,965,769 | $73.69M |
| Peter Kolchinsky | Director | 1,500,000 | $22.26M |
| Ryan Martins | Chief Financial Officer | 374,295 | $5.55M |
| RA Capital Nexus Fund, L.P. | Director | 335,364 | $4.98M |
| Edward Morrow Atkinson III | Director | 6,250 | $92.75K |
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 ETNB 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.