Quick Takeaways
- James N. Topper has 4 issuer positions tracked on this page.
- Estimated disclosed ownership value: $182,520,102.
- Recent insider filing activity is available below.
- Info
- Significant Ownership
- Insider Ownership
Insider Trading & Ownership of James N. Topper
- Location
- Palo Alto, CA
- Summary
- The estimated net worth of James N. Topper is at least $182,520,102 dollars as of 17 Sep 2025. James N. Topper is the Director of NewAmsterdam Pharma Co N.V. and owns shares of NewAmsterdam Pharma Co N.V. (NAMS) stock worth about $162.8M. James N. Topper is the Director, 10%+ Owner of Phathom Pharmaceuticals, Inc. and owns shares of Phathom Pharmaceuticals, Inc. (PHAT) stock worth about $19.64M. James N. Topper is the Director, 10%+ Owner of ANAPTYSBIO, INC and owns shares of ANAPTYSBIO, INC (ANAB) stock worth about $85.1K.
- Signature
- /s/ Steve R. Bailey, Attorney-in-Fact For James N. Topper
- All Insider Reports
- All Insider Reports
Follow Filing Activity
Follow James N. Topper and return when a new Insider Trading filing changes the record on this page.
This uses the existing product follow flow to surface future filing-backed changes without guessing what they mean.
What Changed
- Largest disclosed position: NewAmsterdam Pharma Co N.V. ($162,795,734).
- Past-year value change for that position: +$295,267.
Why This Matters
- This page translates Forms 3/4/5 into a quick ownership context before you inspect each transaction row.
- You can cross-check role, issuer, and filing chronology directly against the SEC source.
Source Evidence
Filed on Form 4
See Original Filing
Insider ownership context is sourced from SEC Forms 3, 4, and 5.
Ownership of James N. Topper
| Symbol | Company | Relationship | Holdings Value | Past Year Net Change | Change % | Report Period |
|---|---|---|---|---|---|---|
| NAMS, NAMSW | NewAmsterdam Pharma Co N.V. | Director | $162,795,734 | +$295,267 | +0.18% | 15 Sep 2025 |
| PHAT | Phathom Pharmaceuticals, Inc. | Director, 10%+ Owner | $19,639,309 | +$191,988 | +0.99% | 03 Jun 2025 |
| ANAB | ANAPTYSBIO, INC | Director, 10%+ Owner | $85,059 | 06 Jan 2023 | ||
| ALPN | ALPINE IMMUNE SCIENCES, INC. | Director | $0 | 18 May 2024 |
Insider Transactions Reported by James N. Topper:
| Sym | Company | Class | Transaction | % | Value $ | * Price $ | Shares | Shares After | Date | Ownership |
|---|
* An asterisk sign (*) next to the price indicates that the price is likely invalid.