Spero TherapeuticsSPRO
13F holders, Q2 2025 (June 30)At the end of Q2 2025, 44 institutions reported holding Spero Therapeutics Inc. (SPRO) in their 13F filings, up 6 from Q1 2025. 16 opened new positions and 10 sold out. The largest holders were Pfizer Inc ($6.9M), Vanguard Group Inc. ($5.7M) and Anson Funds Management LP ($4.7M). 2 famous investors held it, including Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio) and Ken Griffin (0.0% of Citadel Advisors's portfolio).
- Company
- Spero Therapeutics Inc.
- CUSIP
- 84833T103
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q1 2025 → Q2 2025
| Institutions | Total Value | |
|---|---|---|
| New Positions | 16 | $3.8M |
| Exits | 10 | $1.2M |
All 13F filers, Q1 2025 → Q2 2025: 1,584,300 shares bought and 5,613,612 shares sold, net −4,029,312 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 44 holders
| Pfizer Inc | 1.19% | No change | 2,362,348 | $6.9M |
| Vanguard Group Inc. | 0.00% | Add +10.6% | 1,950,381 | $5.7M |
| Anson Funds Management LP | 0.87% | Reduce -57.5% | 1,615,469 | $4.7M |
| Alphabet Inc. | 0.12% | No change | 889,979 | $2.6M |
| Renaissance Technologies | 0.00% | Reduce -14.3% | 832,165 | $2.4M |
| Schonfeld Strategic Advisors LLC | 0.01% | New | 510,834 | $1.5M |
| Geode Capital Management, LLC | 0.00% | Reduce -2.7% | 510,699 | $1.5M |
| BlackRock, Inc. | 0.00% | Reduce -9.8% | 434,768 | $1.3M |
| Monimus Capital Management, LP | 0.72% | No change | 310,908 | $902K |
| Informed Momentum Co LLC | 0.10% | New | 239,140 | $694K |
| Stonepine Capital Management, LLC | 0.45% | New | 156,888 | $455K |
| State Street Corp. | 0.00% | Add +3.0% | 153,451 | $445K |
| Ionic Capital Management LLC | 0.67% | New | 150,000 | $435K |
| ADAR1 Capital Management, LLC | 0.07% | Reduce -82.0% | 143,917 | $417K |
| Bridgeway Capital Management, LLC | 0.01% | Reduce -25.8% | 114,800 | $333K |
| Acadian Asset Management LLC | 0.00% | Reduce -87.0% | 112,889 | $327K |
| Citadel Advisors | 0.00% | Add +69.3% | 103,786 | $301K |
| Northern Trust Corp. | 0.00% | Reduce -0.1% | 100,831 | $292K |
| Susquehanna International Group, LLP | 0.00% | New | 69,814 | $202K |
| XTX Topco Ltd | 0.00% | New | 34,551 | $100K |
| Capital Asset Advisory Services LLC | 0.00% | New | 32,548 | $94K |
| Axxcess Wealth Management, LLC | 0.00% | New | 32,548 | $94K |
| Quadrature Capital Ltd | 0.00% | New | 31,205 | $90K |
| Three Seasons Wealth, LLC | 0.01% | No change | 30,000 | $87K |
| Simplex Trading, LLC | 0.00% | Add +494.8% | 30,322 | $87K |
| Charles Schwab Investment Management Inc. | 0.00% | No change | 28,565 | $83K |
| Cubist Systematic Strategies, LLC | 0.00% | New | 27,140 | $79K |
| Invesco Ltd. | 0.00% | New | 14,968 | $43K |
| Texas Yale Capital Corp. | 0.00% | No change | 10,000 | $29K |
| Morgan Stanley | 0.00% | Add +32.3% | 9,221 | $27K |
| Group One Trading LLC | 0.00% | New | 8,239 | $24K |
| UBS Group AG | 0.00% | Add +189.9% | 8,194 | $24K |
| Royal Bank of Canada | 0.00% | New | 5,739 | $17K |
| Bank of America Corp. | 0.00% | Add +1.2% | 5,633 | $16K |
| Raymond James Financial Inc. | 0.00% | New | 3,082 | $9K |
| Cullen/Frost Bankers, Inc. | 0.00% | No change | 2,000 | $6K |
| Tower Research Capital LLC (TRC) | 0.00% | New | 603 | $2K |
| Osaic Holdings, Inc. | 0.00% | New | 290 | $841 |
| JPMorgan Chase & Co. | 0.00% | Reduce -99.6% | 236 | $684 |
| Wells Fargo & Company | 0.00% | No change | 200 | $580 |
| US Bancorp \de | 0.00% | No change | 151 | $438 |
| NewEdge Advisors, LLC | 0.00% | No change | 100 | $290 |
| SBI Securities Co., Ltd. | 0.00% | Add +3.3% | 62 | $180 |
| BNP Paribas Financial Markets | 0.00% | Add +233.3% | 40 | $116 |
"% of holder's portfolio" is SPRO's weight in each manager's 13F, not the share of Spero Therapeutics Inc. the manager owns.