UPB

Upstream Bio Inc

78 hedge funds and large institutions have $261M invested in Upstream Bio Inc in 2025 Q1 according to their latest regulatory filings, with 23 funds opening new positions, 11 increasing their positions, 25 reducing their positions, and 15 closing their positions.

New
Increased
Maintained
Reduced
Closed

more first-time investments, than exits

New positions opened: | Existing positions closed:

more funds holding

Funds holding:

more ownership

Funds ownership:

less funds holding in top 10

Funds holding in top 10:

56% less repeat investments, than reductions

Existing positions increased: 11 | Existing positions reduced: 25

62% less capital invested

Capital invested by funds: $690M → $261M (-$429M)

Holders
78
Holders Change
Holders Change %
% of All Funds
Holding in Top 10
4
Holding in Top 10 Change
Holding in Top 10 Change %
% of All Funds
New
Increased
Reduced
Closed
Calls
Puts
Net Calls
Net Calls Change
Name Holding Trade Value Shares
Change
Change in
Stake
26
$843K
27
$809K
28
$805K
29
$655K
30
$520K
31
$378K
32
$367K
33
$315K
34
$239K
35
$226K
36
$202K
37
$153K
38
$138K
39
$133K
40
$130K
41
$115K
42
$111K
43
$93.7K
44
$93.5K
45
$93.2K
46
$93K
47
$93K
48
$91.8K
49
$81.6K
50
$77.9K