# MBX BIOSCIENCES INC COM

MBX BIOSCIENCES INC COM is a security (CUSIP 55287L101) tracked across SEC portfolio filings. 157 institutional managers reported $1.6B on Form 13F as of 2026-06-30; 18 registered fund positions totaling $56.6M via N-PORT as of 2026-05-31.

## Summary

- Issuer: MBX BIOSCIENCES INC
- Class: COM
- CUSIP: 55287L101
- Asset category: EC
- 13F holders: 157
- 13F value: $1.6B
- 13F period: 2026-06-30
- N-PORT fund positions: 18
- N-PORT value: $56.6M
- N-PORT report: 2026-05-31

## Top institutional holders (Form 13F)

_Showing 15 of 157 managers by value._

| Manager | Location | Value | Shares |
| --- | --- | --- | --- |
| [Frazier Life Sciences Management, L.P.](https://search.stillhousedata.com/firm/317522) | MENLO PARK, CA | $198.6M | 6,652,013 |
| [ORBIMED ADVISORS LLC](https://search.stillhousedata.com/firm/118608) | New York, NY | $108.6M | 3,637,887 |
| [NEA Management Company, LLC](https://search.stillhousedata.com/firm/161004) | TIMONIUM, MD | $107.9M | 3,614,486 |
| WELLINGTON MANAGEMENT GROUP LLP | BOSTON, MA | $95.3M | 3,191,824 |
| BlackRock, Inc. | New York, NY | $87.8M | 2,941,406 |
| FMR LLC | BOSTON, MA | $87.7M | 2,936,684 |
| Deep Track Capital, LP | GREENWICH, CT | $82.3M | 2,757,569 |
| [Aaron Wealth Advisors LLC](https://search.stillhousedata.com/firm/298079) | Chicago, IL | $64.5M | 1,167,799 |
| NVP Associates, LLC | Menlo Park, CA | $63.8M | 2,136,335 |
| [VANGUARD GROUP INC](https://search.stillhousedata.com/firm/105958) | Valley Forge, PA | $57.3M | 1,817,811 |
| [Polar Capital Holdings Plc](https://search.stillhousedata.com/firm/136133) | London, X0 | $48.4M | 1,622,186 |
| [BRAIDWELL LP](https://search.stillhousedata.com/firm/316988) | STAMFORD, CT | $44.6M | 1,492,467 |
| [Cormorant Asset Management, LP](https://search.stillhousedata.com/firm/167820) | BOSTON, MA | $33.4M | 1,120,000 |
| Driehaus Capital Management LLC | Chicago, IL | $30.4M | 1,018,212 |
| [CITADEL ADVISORS LLC](https://search.stillhousedata.com/firm/148826) | MIAMI, FL | $28.9M | 932,833 |

## Top fund holders (N-PORT)

_Showing 15 of 18 fund positions by value._

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [T. Rowe Price Health Sciences Fund, Inc.](https://search.stillhousedata.com/fund/S000002088) | T. ROWE PRICE HEALTH SCIENCES FUND, INC. | $21.5M | 19.77% |
| [Fidelity Advisor Health Care Fund](https://search.stillhousedata.com/fund/S000005329) | Fidelity Advisor Series VII | $9.1M | 31.40% |
| [VANGUARD EXTENDED MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002841) | VANGUARD INDEX FUNDS | $8.4M | 1.04% |
| [VANGUARD RUSSELL 2000 INDEX FUND](https://search.stillhousedata.com/fund/S000030003) | VANGUARD SCOTTSDALE FUNDS | $4.6M | 2.63% |
| BlackRock Health Sciences Term Trust | BlackRock Health Sciences Term Trust | $3.8M | 37.91% |
| [VANGUARD U.S. MOMENTUM FACTOR ETF](https://search.stillhousedata.com/fund/S000061302) | VANGUARD WELLINGTON FUND | $2.1M | 11.63% |
| [Master Small Cap Index Series](https://search.stillhousedata.com/fund/S000002716) | Quantitative Master Series LLC | $1.3M | 2.78% |
| [T. Rowe Price Health Sciences Portfolio](https://search.stillhousedata.com/fund/S000002083) | T. ROWE PRICE EQUITY SERIES, INC. | $1.3M | 19.83% |
| [HARTFORD SMALL COMPANY HLS FUND](https://search.stillhousedata.com/fund/S000003220) | HARTFORD SERIES FUND INC | $937K | 24.09% |
| BlackRock Health Sciences Trust | BlackRock Health Sciences Trust | $849K | 15.95% |
| [VANGUARD BALANCED INDEX FUND](https://search.stillhousedata.com/fund/S000002560) | VANGUARD VALLEY FORGE FUNDS | $575K | 0.10% |
| [U.S. MICRO CAP PORTFOLIO](https://search.stillhousedata.com/fund/S000000948) | DFA INVESTMENT DIMENSIONS GROUP INC | $508K | 0.68% |
| [VANGUARD INSTITUTIONAL TOTAL STOCK MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002855) | VANGUARD INSTITUTIONAL INDEX FUNDS | $492K | 0.16% |
| [Fidelity Nasdaq Composite Index ETF](https://search.stillhousedata.com/fund/S000006011) | Fidelity Commonwealth Trust | $443K | 0.41% |
| [Goldman Sachs ActiveBeta(R) U.S. Small Cap Equity ETF](https://search.stillhousedata.com/fund/S000048296) | Goldman Sachs ETF Trust | $241K | 2.44% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/55287L101.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.