Spero Therapeutics
SPRO
50 hedge funds and large institutions have $49.3M invested in Spero Therapeutics in 2026 Q1 according to their latest regulatory filings, with 8 funds opening new positions, 13 increasing their positions, 10 reducing their positions, and 12 closing their positions.
100% more funds holding in top 10
Funds holding in top 10: 1 → 2 (+1)
30% more repeat investments, than reductions
Existing positions increased: 13 | Existing positions reduced: 10
0% more capital invested
Capital invested by funds: $49.2M → $49.3M (+$71.4K)
1.1% less ownership
Funds ownership: 37.49% → 36.39% (-1.1%)
11% less funds holding
Funds holding: 56 → 50 (-6)
33% less first-time investments, than exits
New positions opened: 8 | Existing positions closed: 12
45% less call options, than puts
Call options by funds: $194K | Put options by funds: $350K
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Two Sigma Investments
New York
|
+$1.22M |
| 2 |
AFM
Anson Funds Management
Dallas,
Texas
|
+$519K |
| 3 |
Marshall Wace
London,
United Kingdom
|
+$373K |
| 4 |
GCP
GSA Capital Partners
London,
United Kingdom
|
+$236K |
| 5 |
Squarepoint
New York
|
+$178K |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
EI
EAM Investors
Solana Beach,
California
|
-$508K |
| 2 |
IFO
Intrepid Family Office
Sarasota,
Florida
|
-$353K |
| 3 |
SEI Investments
Oaks,
Pennsylvania
|
-$308K |
| 4 |
UBS Group
Zurich,
Switzerland
|
-$269K |
| 5 |
ACM
ADAR1 Capital Management
Austin,
Texas
|
-$265K |
| Name | Holding | Trade Value |
Shares Change |
Change in Stake |
|
|---|---|---|---|---|---|
|
EI
51
EAM Investors
Solana Beach,
California
| – | -$508K | -218,084 | Closed |
|
52
Two Sigma Advisers
New York
| – | -$505K | -216,600 | Closed |
|
|
53
SEI Investments
Oaks,
Pennsylvania
| – | -$308K | -132,010 | Closed |
|
|
ACM
54
ADAR1 Capital Management
Austin,
Texas
| – | -$265K | -113,839 | Closed |
|
|
AWM
55
Axxcess Wealth Management
Carlsbad,
California
| – | -$75.8K | -32,548 | Closed |
|
56
Millennium Management
New York
| – | -$56.2K | -24,107 | Closed |
|
|
XT
57
XTX Topco
George Town,
Cayman Islands
| – | -$35.4K | -15,175 | Closed |
|
|
TYCC
58
Texas Yale Capital Corp
St. Petersburg,
Florida
| – | -$23.3K | -10,000 | Closed |
|
|
TRCT
59
Tower Research Capital (TRC)
New York
| – | -$16.8K | -7,215 | Closed |
|
|
CFB
60
Cullen/Frost Bankers
San Antonio,
Texas
| – | -$6.99K | -3,000 | Closed |
|
61
Bank of America
Charlotte,
North Carolina
| – | -$1.73K | -744 | Closed |
|
62
Rockefeller Capital Management
New York
| – | -$466 | -200 | Closed |
|
SPRO Hedge Fund Activity: Q1 2026 in Review
50 of the 8,126 institutional investors tracked by Wall St. Rank reported a position in Spero Therapeutics (SPRO) for Q1 2026, worth a combined $49.3M — up 0.15% from $49.2M a quarter earlier.
Sellers outnumbered buyers: 12 funds closed out of SPRO and 8 opened new positions — a net loss of 4 holders — while 10 trimmed existing stakes and 13 added.
The largest buyer was Two Sigma Investments, adding an estimated $1.22M. The largest seller was EAM Investors, exiting entirely with an estimated $508K sold.
- 50 institutional investors held Spero Therapeutics (SPRO) as of Q1 2026, down from 56 in Q4 2025.
- Funds reported $49.3M of Spero Therapeutics stock for Q1 2026, up 0.15% quarter-over-quarter.
- 8 funds opened new Spero Therapeutics positions in Q1 2026 and 12 closed out, a net change of -4 holders.
- The largest Spero Therapeutics buyer in Q1 2026 was Two Sigma Investments, an estimated $1.22M added.
- The largest Spero Therapeutics seller in Q1 2026 was EAM Investors, an estimated $508K sold.
Based on aggregated 13F filings for Q1 2026.