Spero Therapeutics
SPRO
50 hedge funds and large institutions have $48.3M invested in Spero Therapeutics in 2026 Q1 according to their latest regulatory filings, with 8 funds opening new positions, 12 increasing their positions, 11 reducing their positions, and 13 closing their positions.
100% more funds holding in top 10
Funds holding in top 10: 1 → 2 (+1)
9% more repeat investments, than reductions
Existing positions increased: 12 | Existing positions reduced: 11
2% less capital invested
Capital invested by funds: $49.2M → $48.3M (-$916K)
1.83% less ownership
Funds ownership: 37.49% → 35.66% (-1.8%)
11% less funds holding
Funds holding: 56 → 50 (-6)
38% less first-time investments, than exits
New positions opened: 8 | Existing positions closed: 13
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 |
Marshall Wace
London,
United Kingdom
|
+$373K |
| 3 |
GCP
GSA Capital Partners
London,
United Kingdom
|
+$236K |
| 4 |
Squarepoint
New York
|
+$178K |
| 5 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
+$93.5K |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
EI
EAM Investors
Solana Beach,
California
|
-$508K |
| 2 |
AFM
Anson Funds Management
Dallas,
Texas
|
-$482K |
| 3 |
IFO
Intrepid Family Office
Sarasota,
Florida
|
-$353K |
| 4 |
SEI Investments
Oaks,
Pennsylvania
|
-$308K |
| 5 |
UBS Group
Zurich,
Switzerland
|
-$269K |
SPRO Hedge Fund Activity: Q1 2026 in Review
50 of the 8,206 institutional investors tracked by Wall St. Rank reported a position in Spero Therapeutics (SPRO) for Q1 2026, worth a combined $48.3M — down 1.9% from $49.2M a quarter earlier.
Sellers outnumbered buyers: 13 funds closed out of SPRO and 8 opened new positions — a net loss of 5 holders — while 11 trimmed existing stakes and 12 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 $48.3M of Spero Therapeutics stock for Q1 2026, down 1.9% quarter-over-quarter.
- 8 funds opened new Spero Therapeutics positions in Q1 2026 and 13 closed out, a net change of -5 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.