Upstream Bio Inc
UPB
79 hedge funds and large institutions have $267M invested in Upstream Bio Inc in 2025 Q1 according to their latest regulatory filings, with 23 funds opening new positions, 11 increasing their positions, 26 reducing their positions, and 14 closing their positions.
64% more first-time investments, than exits
New positions opened: 23 | Existing positions closed: 14
13% more funds holding
Funds holding: 70 → 79 (+9)
7.78% more ownership
Funds ownership: 78.5% → 86.28% (+7.8%)
33% less funds holding in top 10
Funds holding in top 10: 6 → 4 (-2)
58% less repeat investments, than reductions
Existing positions increased: 11 | Existing positions reduced: 26
61% less capital invested
Capital invested by funds: $690M → $267M (-$423M)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
AS
Altshuler Shaham
Tel Aviv,
Israel
|
+$30.9M |
| 2 |
DTC
Deep Track Capital
Greenwich,
Connecticut
|
+$12.4M |
| 3 |
PHP
Parkman Healthcare Partners
Stamford,
Connecticut
|
+$2.23M |
| 4 |
SSA
Schonfeld Strategic Advisors
New York
|
+$1.7M |
| 5 |
VCIM
Velan Capital Investment Management
Alpharetta,
Georgia
|
+$1.02M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Balyasny Asset Management
Chicago,
Illinois
|
-$4.95M |
| 2 |
Citadel Advisors
Miami,
Florida
|
-$2.96M |
| 3 |
Wellington Management Group
Boston,
Massachusetts
|
-$2.58M |
| 4 |
SB
Samsara BioCapital
Palo Alto,
California
|
-$1.43M |
| 5 |
MAP
Moody Aldrich Partners
Marblehead,
Massachusetts
|
-$1.23M |
UPB Hedge Fund Activity: Q1 2025 in Review
79 of the 7,458 institutional investors tracked by Wall St. Rank reported a position in Upstream Bio Inc (UPB) for Q1 2025, worth a combined $267M — down 61% from $690M a quarter earlier.
Buyers outnumbered sellers: 23 funds opened new UPB positions and 14 closed out — a net gain of 9 holders — while 11 added to existing stakes and 26 trimmed.
The largest buyer was Altshuler Shaham, opening a new position worth an estimated $30.9M. The largest seller was Balyasny Asset Management, exiting entirely with an estimated $4.95M sold.
- 79 institutional investors held Upstream Bio Inc (UPB) as of Q1 2025, up from 70 in Q4 2024.
- Funds reported $267M of Upstream Bio Inc stock for Q1 2025, down 61% quarter-over-quarter.
- 23 funds opened new Upstream Bio Inc positions in Q1 2025 and 14 closed out, a net change of +9 holders.
- The largest Upstream Bio Inc buyer in Q1 2025 was Altshuler Shaham, an estimated $30.9M added.
- The largest Upstream Bio Inc seller in Q1 2025 was Balyasny Asset Management, an estimated $4.95M sold.
Based on aggregated 13F filings for Q1 2025.