Topper James N — SEC Form 4 filings
SEC reporting owner CIK 1341382. 21 Form 4 filings on record with FilingPulse; latest filed 2026-05-21.
Transaction summary — filings shown
Covers all 21 filings on record, filed 2024-03-28 to 2026-05-21. Counts and totals are arithmetic on values as filed — descriptive data, not a recommendation.
- Open-market purchases (code P, non-derivative): 18 legs across 14 filings — 1,388,243 shares, $22,906,516 total (shares × price as filed).
- Open-market sales (code S, non-derivative): 1 leg across 1 filing — 19 shares, $1,227 total (shares × price as filed).
- Other reported legs (grants, option exercises, tax withholding, gifts, derivative-security transactions, …): 20.
- Largest priced transaction: purchase of 666,666 shares @ $18.00 ($11,999,988) in MBX Biosciences, Inc., filed 2025-09-30.
By issuer — same filings
Open-market purchase/sale legs on non-derivative securities, grouped by issuer. Role is as filed on the newest filing for that issuer. Dollar totals cover priced legs only (shares × price as filed). Ordered by priced transaction value, largest first.
| Issuer | Role (as filed) | Filings | Purchases (P) | Sales (S) | Other legs |
|---|---|---|---|---|---|
| MBX Biosciences, Inc. (MBX) | 10% owner | 2 | 2 legs · 1,291,666 sh · $21,999,988 | — | 3 |
| NewAmsterdam Pharma Co N.V. (NAMS) | Director | 8 | 9 legs · 28,324 sh · $586,215 | — | — |
| Phathom Pharmaceuticals, Inc. (PHAT) | Director, 10% owner | 6 | 6 legs · 59,403 sh · $191,988 | — | 5 |
| HilleVax, Inc. (HLVX) | 10% owner | 3 | 1 leg · 8,850 sh · $128,325 | — | 2 |
| ALPINE IMMUNE SCIENCES, INC. (ALPN) | Director | 2 | — | 1 leg · 19 sh · $1,227 | 10 |
Form 4 filings — Topper James N
| Filed | Form | Issuer | Reported transactions | Source |
|---|---|---|---|---|
| 2026-05-21 | 4 | Phathom Pharmaceuticals, Inc. (PHAT) | Grant/award (A): 24,122 @ $0 | EDGAR |
| 2025-09-30 | 4 | MBX Biosciences, Inc. (MBX) jointly with Heron Patrick J, FHMLS X, L.P., FHMLS X, L.L.C., Frazier Life Sciences X, L.P. | Purchase (P): 666,666 @ $18 | EDGAR |
| 2025-09-17 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 660 @ $23.70 | EDGAR |
| 2025-09-17 | 4 | HilleVax, Inc. (HLVX) jointly with Frazier Life Sciences X, L.P., FHMLS X, L.P., FHMLS X, L.L.C., Heron Patrick J | Code (U): 8,535,337 @ $1.95 · Code (U): 17,199 @ $1.95 | EDGAR |
| 2025-09-10 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 1,260 @ $24.99 | EDGAR |
| 2025-08-13 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 471 @ $23.98 | EDGAR |
| 2025-06-26 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 2,520 @ $18.43 · Purchase (P): 1,260 @ $18.26 | EDGAR |
| 2025-06-18 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 8,584 @ $19.50 | EDGAR |
| 2025-06-05 | 4 | Phathom Pharmaceuticals, Inc. (PHAT) | Grant/award (A): 10,500 @ $0 · Grant/award (A): 17,500 (derivative) @ $0 | EDGAR |
| 2025-05-23 | 4 | Phathom Pharmaceuticals, Inc. (PHAT) | Purchase (P): 3,780 @ $3.86 | EDGAR |
| 2025-05-15 | 4 | Phathom Pharmaceuticals, Inc. (PHAT) | Purchase (P): 1,120 @ $3.16 · Purchase (P): 6,300 @ $3.32 | EDGAR |
| 2025-05-13 | 4 | Phathom Pharmaceuticals, Inc. (PHAT) | Purchase (P): 33,376 @ $3.19 · Purchase (P): 2,226 @ $3.62 · Purchase (P): 12,601 @ $3.04 | EDGAR |
| 2025-03-28 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 1,135 @ $22.49 | EDGAR |
| 2025-03-06 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 4,005 @ $21.02 | EDGAR |
| 2024-09-17 | 4 | MBX Biosciences, Inc. (MBX) jointly with Frazier Life Sciences X, L.P., FHMLS X, L.P., FHMLS X, L.L.C. | Conversion (C): 3,927,774 · Purchase (P): 625,000 @ $16 · Conversion (C): 18,922,852 (derivative) · Conversion (C): 28,297,265 (derivative) | EDGAR |
| 2024-05-31 | 4/A | HilleVax, Inc. (HLVX) jointly with Frazier Life Sciences X, L.P., FHMLS X, L.P., FHMLS X, L.L.C., Heron Patrick J | Holdings only — no transactions reported | EDGAR |
| 2024-05-24 | 4 | Phathom Pharmaceuticals, Inc. (PHAT) | Grant/award (A): 10,500 @ $0 · Grant/award (A): 17,500 (derivative) @ $0 | EDGAR |
| 2024-05-20 | 4 | ALPINE IMMUNE SCIENCES, INC. (ALPN) | Code (U): 2,829,347 · Disposition to issuer (D): 7,650 (derivative) · Disposition to issuer (D): 7,650 (derivative) · Disposition to issuer (D): 7,650 (derivative) · Disposition to issuer (D): 7,650 (derivative) · Disposition to issuer (D): 10,000 (derivative) · +2 more | EDGAR |
| 2024-04-29 | 4 | ALPINE IMMUNE SCIENCES, INC. (ALPN) | Option exercise/expiry (X): 1,200,000 @ $0.00 · Sale (S): 19 @ $64.57 · Option exercise/expiry (X): 1,200,000 (derivative) @ $0 | EDGAR |
| 2024-04-08 | 4 | HilleVax, Inc. (HLVX) jointly with Frazier Life Sciences X, L.P., FHMLS X, L.P., FHMLS X, L.L.C., Heron Patrick J | Purchase (P): 8,850 @ $14.50 | EDGAR |
| 2024-03-28 | 4 | NewAmsterdam Pharma Co N.V. (NAMS) | Purchase (P): 8,429 @ $21.50 | EDGAR |
FilingPulse's Form 4 archive currently extends back to 2024-01-11 and is expanding backward through EDGAR history — earlier filings by this insider may not be indexed yet. Names and roles are shown as filed.
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