# UPSTREAM BIO INC COM

UPSTREAM BIO INC COM is a security (CUSIP 91678A107) tracked across SEC portfolio filings. 138 institutional managers reported $428.7M on Form 13F as of 2026-06-30; 17 registered fund positions totaling $12.0M via N-PORT as of 2026-05-31.

## Summary

- Issuer: UPSTREAM BIO INC
- Class: COM
- CUSIP: 91678A107
- Asset category: EC
- 13F holders: 138
- 13F value: $428.7M
- 13F period: 2026-06-30
- N-PORT fund positions: 17
- N-PORT value: $12.0M
- N-PORT report: 2026-05-31

## Top institutional holders (Form 13F)

_Showing 15 of 138 managers by value._

| Manager | Location | Value | Shares |
| --- | --- | --- | --- |
| FMR LLC | BOSTON, MA | $72.9M | 8,101,563 |
| [VANGUARD GROUP INC](https://search.stillhousedata.com/firm/105958) | Valley Forge, PA | $64.8M | 2,388,439 |
| [ORBIMED ADVISORS LLC](https://search.stillhousedata.com/firm/118608) | New York, NY | $51.2M | 5,693,589 |
| BlackRock, Inc. | New York, NY | $26.0M | 3,753,358 |
| Decheng Capital LLC | MENLO PARK, CA | $24.5M | 2,724,868 |
| ENAVATE SCIENCES GP, LLC | New York, NY | $22.1M | 2,459,703 |
| FEDERATED HERMES, INC. | Pittsburgh, PA | $8.8M | 979,758 |
| [GEODE CAPITAL MANAGEMENT, LLC](https://search.stillhousedata.com/firm/115504) | BOSTON, MA | $8.6M | 950,617 |
| MILLENNIUM MANAGEMENT LLC | NEW YORK, NY | $8.4M | 937,323 |
| Bain Capital Life Sciences Investors, LLC | Boston, MA | $7.8M | 867,211 |
| [Woodline Partners LP](https://search.stillhousedata.com/firm/301480) | San Francisco, CA | $7.5M | 831,481 |
| D. E. Shaw & Co., Inc. | New York, NY | $7.4M | 820,480 |
| [Parkman Healthcare Partners LLC](https://search.stillhousedata.com/firm/300701) | STAMFORD, CT | $7.1M | 786,783 |
| [Samsara BioCapital, LLC](https://search.stillhousedata.com/firm/288114) | Palo Alto, CA | $6.6M | 736,047 |
| SEB Asset Management AB | STOCKHOLM, V7 | $6.1M | 878,473 |

## Top fund holders (N-PORT)

_Showing 15 of 17 fund positions by value._

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [Fidelity Advisor Health Care Fund](https://search.stillhousedata.com/fund/S000005329) | Fidelity Advisor Series VII | $3.7M | 12.72% |
| [VANGUARD EXTENDED MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002841) | VANGUARD INDEX FUNDS | $3.5M | 0.42% |
| [VANGUARD RUSSELL 2000 INDEX FUND](https://search.stillhousedata.com/fund/S000030003) | VANGUARD SCOTTSDALE FUNDS | $1.4M | 0.80% |
| [VANGUARD MARKET NEUTRAL FUND](https://search.stillhousedata.com/fund/S000019457) | VANGUARD MONTGOMERY FUNDS | $1.1M | 25.01% |
| BlackRock Health Sciences Term Trust | BlackRock Health Sciences Term Trust | $509K | 5.03% |
| [Master Small Cap Index Series](https://search.stillhousedata.com/fund/S000002716) | Quantitative Master Series LLC | $495K | 1.03% |
| BlackRock Health Sciences Trust | BlackRock Health Sciences Trust | $270K | 5.08% |
| [U.S. MICRO CAP PORTFOLIO](https://search.stillhousedata.com/fund/S000000948) | DFA INVESTMENT DIMENSIONS GROUP INC | $258K | 0.34% |
| [VANGUARD BALANCED INDEX FUND](https://search.stillhousedata.com/fund/S000002560) | VANGUARD VALLEY FORGE FUNDS | $238K | 0.04% |
| [VANGUARD GROWTH AND INCOME FUND](https://search.stillhousedata.com/fund/S000002913) | VANGUARD QUANTITATIVE FUNDS | $236K | 0.14% |
| [Fidelity Disruptive Medicine ETF](https://search.stillhousedata.com/fund/S000079688) | Fidelity Covington Trust | $208K | 50.80% |
| [VANGUARD INSTITUTIONAL TOTAL STOCK MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002855) | VANGUARD INSTITUTIONAL INDEX FUNDS | $184K | 0.06% |
| [DWS Small Cap Index VIP](https://search.stillhousedata.com/fund/S000006223) | DEUTSCHE DWS INVESTMENTS VIT FUNDS | $42K | 1.01% |
| Gabelli Healthcare & WellnessRx Trust | Gabelli Healthcare & WellnessRx Trust | $7K | 0.49% |
| [TIAA Separate Account VA-1 - Stock Index Account](https://search.stillhousedata.com/fund/S000005098) | TIAA Separate Account VA-1 | $5K | 0.04% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/91678A107.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

---

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.