MBX · Insider trading · 13F holders · Congress trades
MBX Biosciences, Inc. (MBX)
Who is buying and selling MBX: company insiders on SEC Form 4, hedge funds and superinvestors on Form 13F, and members of Congress under the STOCK Act. Every figure links to the filing or page it comes from.
- 13F filers holding
- 23
- Insider buys, 90 days
- $0
- Insider sales, 90 days
- $24K
- Congress trades, 12 months
- 0
MBX at a glance
- Between Aug 1, 2026 and Oct 29, 2026, 1 MBX insider filed 1 sale worth $24K on SEC Form 4, and no open-market purchases.
- 23 13F filers hold MBX among their 50 largest positions, worth $1.5B combined, including Oleg Nodelman. The biggest bets by portfolio weight are NEA Management Company, LLC (12.6%), Frazier Life Sciences Management, L.P. (8.0%) and KVP Capital Advisors, LP (4.9%). In their latest 13Fs, 1 manager opened a new position and 1 added to one.
- No member of Congress has disclosed a trade in MBX.
- MBX last closed at $54.54 on Oct 29, 2026.
MBX insider trading
Between Aug 1, 2026 and Oct 29, 2026, 1 MBX insider filed 1 sale worth $24K on SEC Form 4, and no open-market purchases.
| Filed | Insider | Role | Trade | Shares | Price | Value | Form 4 |
|---|---|---|---|---|---|---|---|
| Aug 5, 2026 | Azoulay Salomon | Chief Medical Officer | Sale | 370 | $65.77 | $24K | SEC |
Who owns MBX? Hedge funds and superinvestors
23 13F filers hold MBX among their 50 largest positions, worth $1.5B combined, including Oleg Nodelman. The biggest bets by portfolio weight are NEA Management Company, LLC (12.6%), Frazier Life Sciences Management, L.P. (8.0%) and KVP Capital Advisors, LP (4.9%). In their latest 13Fs, 1 manager opened a new position and 1 added to one.
Superinvestors holding MBX: Oleg Nodelman 1.1%
| Manager | % of portfolio | Value | Shares | Last quarter | 13F |
|---|---|---|---|---|---|
| Frazier Life Sciences Management, L.P.Hedge fund | 8.0% | $367.2M | 6,652,013 | +0.0% shares | Q2 2026 |
| NEA Management Company, LLCHedge fund | 12.6% | $199.5M | 3,614,486 | +0.0% shares | Q2 2026 |
| Orbimed Advisors LLCHedge fund | 3.6% | $189.3M | 3,428,736 | -5.7% shares | Q2 2026 |
| Paradigm Biocapital Advisors LPHedge fund | 2.6% | $138.4M | 2,508,015 | New | Q2 2026 |
| Nvp Associates, LLCInvestment manager | 35.9% | $117.9M | 2,136,335 | +0.0% shares | Q2 2026 |
| Deep Track Capital, LPHedge fund | 1.4% | $95.6M | 1,732,569 | -37.2% shares | Q2 2026 |
| Aaron Wealth Advisors LLCWealth manager | 3.4% | $68.9M | 1,175,771 | +0.7% shares | Q3 2026 |
| Kynam Capital Management, LPHedge fund | 2.9% | $51.6M | 934,799 | +0.0% shares | Q2 2026 |
| Parkman Healthcare Partners LLCHedge fund | 4.5% | $44.2M | 800,173 | +0.0% shares | Q2 2026 |
| Braidwell LPHedge fund | 1.5% | $39.2M | 710,880 | -52.4% shares | Q2 2026 |
| TCG Crossover Management, LLCHedge fund | 0.9% | $35.9M | 650,000 | +0.0% shares | Q2 2026 |
| Cormorant Asset Management, LPHedge fund | 1.6% | $30.4M | 550,000 | -50.9% shares | Q2 2026 |
| Soleus Capital Management, L.P.Hedge fund | 1.0% | $28.4M | 515,279 | — | Q2 2026 |
| Oleg NodelmanHedge fund | 1.1% | $21.4M | 388,500 | -50.0% shares | Q2 2026 |
| Rock Springs Capital Management LPHedge fund | 0.8% | $16.5M | 298,218 | — | Q2 2026 |
| Opaleye Management Inc.Hedge fund | 1.3% | $14.4M | 260,000 | +0.0% shares | Q2 2026 |
| Tetragon Partners GP LtdHedge fund | 1.8% | $11.2M | 203,543 | +39.9% shares | Q2 2026 |
| Caligan Partners LPHedge fund | 0.5% | $11.0M | 200,000 | -76.4% shares | Q2 2026 |
| KVP Capital Advisors, LPHedge fund | 4.9% | $6.7M | 121,524 | +0.0% shares | Q2 2026 |
| Elmind Capital, LPHedge fund | 1.3% | $5.0M | 91,000 | -56.9% shares | Q2 2026 |
| Koa Wealth Management, LLCWealth manager | 0.6% | $915K | 15,613 | -8.8% shares | Q3 2026 |
| Optimize Financial Inc.Mutual fund manager | 0.3% | $798K | 14,458 | — | Q2 2026 |
| Act Capital Management, LLCHedge fund | 0.3% | $442K | 8,000 | -11.1% shares | Q2 2026 |
Each manager counts with its latest 13F (Q3 2026: 2, Q2 2026: 21). Screen MBX in the grand portfolio →
MBX stock trades by members of Congress
No member of Congress has disclosed a trade in MBX.
MBX questions and answers
Are insiders buying MBX stock?
Between Aug 1, 2026 and Oct 29, 2026, 1 MBX insider filed 1 sale worth $24K on SEC Form 4, and no open-market purchases.
Which hedge funds own MBX?
23 13F filers hold MBX among their 50 largest positions, worth $1.5B combined, including Oleg Nodelman. The biggest bets by portfolio weight are NEA Management Company, LLC (12.6%), Frazier Life Sciences Management, L.P. (8.0%) and KVP Capital Advisors, LP (4.9%). In their latest 13Fs, 1 manager opened a new position and 1 added to one.
Has Congress traded MBX?
No member of Congress has disclosed a trade in MBX.
Who is the largest holder of MBX?
Among 13F filers, Frazier Life Sciences Management, L.P. reports the largest MBX position, $367.2M (6,652,013 shares) in its Q2 2026 13F. The biggest bet by portfolio weight is NEA Management Company, LLC's: 12.6% of its portfolio.
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