UPB

Upstream Bio, Inc. Common Stock
UPB

Overview Fund Activity

78 hedge funds and large institutions have $261M invested in Upstream Bio, Inc. Common Stock in 2025 Q1 according to their latest regulatory filings, with 24 funds opening new positions, 11 increasing their positions, 25 reducing their positions, and 15 closing their positions.

New
Increased
Maintained
Reduced
Closed
Holders
78
Holders Change
+8
Holders Change %
+11.43%
% of All Funds
1.06%
Holding in Top 10
4
Holding in Top 10 Change
-2
Holding in Top 10 Change %
-33.33%
% of All Funds
0.05%
New
24
Increased
11
Reduced
25
Closed
15
Calls
–
Puts
–
Net Calls
–
Net Calls Change
–

Top Buyers

1
DTC
Deep Track Capital
Connecticut
$14.1M
2
AS
Altshuler Shaham
Israel
$3.52M
3
PHP
Parkman Healthcare Partners
Connecticut
$1.43M
4
SSA
Schonfeld Strategic Advisors
New York
$1.09M
5
VCIM
Velan Capital Investment Management
Georgia
$655K

Top Sellers

1
Balyasny Asset Management
Balyasny Asset Management
Illinois
$0
2
Citadel Advisors
Citadel Advisors
Florida
$0
3
Wellington Management Group
Wellington Management Group
Massachusetts
$8.03M
4
MAP
Moody Aldrich Partners
Massachusetts
$0
5
SB
Samsara BioCapital
California
$12.7M
Name Holding Trade Value Shares
Change 		Shares
Change %
Fidelity Investments
1
Fidelity Investments
Massachusetts
$44.4M +$488K +79,672 +1%
O
2
OrbiMed
New York
$34.8M – – –
DC
3
Decheng Capital
California
$20.1M – – –
TCM
4
TCG Crossover Management
California
$17.1M – – –
ES
5
Enavate Sciences
California
$15.1M – – –
DTC
6
Deep Track Capital
Connecticut
$14.1M +$7.95M +1,299,567 +130%
BCLSI
7
Bain Capital Life Sciences Investors
Massachusetts
$14M – – –
VA
8
VR Adviser
New York
$14M – – –
SB
9
Samsara BioCapital
California
$12.7M -$918K -150,000 -7%
OFM
10
Omega Fund Management
Massachusetts
$12.5M – – –
Wellington Management Group
11
Wellington Management Group
Massachusetts
$8.03M -$1.65M -269,697 -17%
BlackRock
12
BlackRock
New York
$7.26M +$416K +67,968 +6%
AllianceBernstein
13
AllianceBernstein
Tennessee
$6.68M -$123K -20,151 -2%
Vanguard Group
14
Vanguard Group
Pennsylvania
$5.55M -$48.9K -7,995 -0.9%
SL
15
Siren LLC
Connecticut
$4.83M -$70.7K -11,550 -1%
NCM
16
Nantahala Capital Management
Connecticut
$3.64M -$30.8K -5,029 -0.8%
AS
17
Altshuler Shaham
Israel
$3.52M +$3.52M +3,235,293 New
WP
18
Woodline Partners
California
$3.41M +$187K +30,552 +6%
Geode Capital Management
19
Geode Capital Management
Massachusetts
$2.51M +$290K +47,408 +13%
Marshall Wace
20
Marshall Wace
United Kingdom
$1.87M +$87.1K +14,229 +5%
GPP
21
Great Point Partners
Connecticut
$1.84M – – –
State Street
22
State Street
Massachusetts
$1.81M +$296K +48,400 +20%
PHP
23
Parkman Healthcare Partners
Connecticut
$1.43M +$1.43M +233,563 New
LCM
24
Lynx1 Capital Management
Puerto Rico
$1.34M -$127K -20,795 -9%
SSA
25
Schonfeld Strategic Advisors
New York
$1.09M +$1.09M +177,984 New
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