Spero Therapeutics, Inc.
SPRO- Exchange
- Nasdaq
- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0001701108
No open-market purchases or sales by Spero Therapeutics, Inc. insiders were filed in the last 90 days; 59 institutions reported holding it in 13F filings for Q2 2026, worth $47.5M in total; no superinvestor holds it.
13F holders, Q1 2026
Institutional positions in Spero Therapeutics, Inc. as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 50
- −5 vs. Q4 2025
- Shares held
- 20.6M
- +1.61M (+8.4%) vs. Q4 2025
- Total value
- $48.3M
- +$3.94M (+8.9%) vs. Q4 2025
- New holders
- 8
- 12 more added
- Sold out
- 13
- 11 more reduced
1 institution that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting SPRO on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 59 | $47.5M |
| Q1 2026 | 50 | $48.3M |
| Q4 2025 | 56 | $49.2M |
| Q3 2025 | 47 | $21.3M |
| Q2 2025 | 44 | $32.1M |
| Q1 2025 | 38 | $10.9M |
| Q4 2024 | 50 | $16.1M |
| Q3 2024 | 46 | $16.5M |
| Q2 2024 | 48 | $18.0M |
| Q1 2024 | 54 | $23.7M |
| Q4 2023 | 50 | $19.6M |
| Q3 2023 | 54 | $17.2M |
| Q2 2023 | 56 | $20.8M |
| Q1 2023 | 48 | $20.6M |
| Q4 2022 | 60 | $24.6M |
| Q3 2022 | 69 | $39.7M |
| Q2 2022 | 79 | $15.5M |
| Q1 2022 | 100 | $176.1M |
| Q4 2021 | 84 | $316.7M |
| Q3 2021 | 88 | $338.3M |
| Q2 2021 | 89 | $244.2M |
| Q1 2021 | 95 | $273.1M |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Spero Therapeutics, Inc.; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Caitong International Asset Management Co., Ltd | 3 | $7 | 0.00% | +3 | New |
| SBI Securities Co., Ltd. | 9 | $21 | 0.00% | 00.0% | Unchanged |
| Farther Finance Advisors, LLC | 10 | $25 | 0.00% | 00.0% | Unchanged |
| BNP Paribas Arbitrage, SA | 40 | $94 | 0.00% | 00.0% | Unchanged |
| US Bancorp | 151 | $353 | 0.00% | 00.0% | Unchanged |
| Wells Fargo & Company | 200 | $468 | 0.00% | 00.0% | Unchanged |
| JPMorgan Chase & Co | 236 | $529 | 0.00% | −5,137−95.6% | Reduced |
| Advisor Group Holdings, Inc. | 290 | $678 | 0.00% | 00.0% | Unchanged |
| UBS Group AG | 3,009 | $7.04K | 0.00% | −113,438−97.4% | Reduced |
| Morgan Stanley | 4,552 | $10.7K | 0.00% | +4,239+1,354.3% | Added |
| FNY Investment Advisers, LLC | 5,300 | $12.0K | 0.01% | 00.0% | Unchanged |
| Jones Financial Companies LLLP | 7,678 | $17.9K | 0.00% | +1,201+18.5% | Added |
| Torrey Growth & Income Advisors | 17,025 | $37.6K | 0.02% | 00.0% | Unchanged |
| Intrepid Family Office LLC | 16,279 | $38.1K | 0.03% | −148,721−90.1% | Reduced |
| Occudo Quantitative Strategies LP | 16,421 | $41.2K | 0.00% | +16,421 | New |
| Assenagon Asset Management S.A. | 18,636 | $43.6K | 0.00% | 00.0% | Unchanged |
| Citigroup Inc | 19,135 | $44.8K | 0.00% | +19,118+112,458.8% | Added |
| Schonfeld Strategic Advisors LLC | 20,314 | $47.5K | 0.00% | +20,314 | New |
| Vanguard Global Advisers, LLC | 25,446 | $59.5K | 0.00% | +25,446 | New |
| Charles Schwab Investment Management Inc | 28,565 | $66.8K | 0.00% | 00.0% | Unchanged |
| Dimensional Fund Advisors LP | 29,768 | $69.2K | 0.00% | 00.0% | Unchanged |
| Three Seasons Wealth, LLC | 30,000 | $70.2K | 0.03% | 00.0% | Unchanged |
| Simplex Trading, LLC | 30,304 | $70.9K | 0.00% | −5,382−15.1% | Reduced |
| Verdad Advisers, LP | 33,455 | $78.3K | 0.09% | +33,455 | New |
| Omers Administration Corp | 39,400 | $92.2K | 0.00% | −91,727−70.0% | Reduced |
| Capital Asset Advisory Services LLC | 32,548 | $92.4K | 0.00% | 00.0% | Unchanged |
| Quadrature Capital Ltd | 40,128 | $93.9K | 0.00% | +2,329+6.2% | Added |
| Invesco Ltd. | 45,374 | $106.2K | 0.00% | +20,669+83.7% | Added |
| Point72 Asset Management, L.P. | 59,668 | $139.6K | 0.00% | +16,089+36.9% | Added |
| Shay Capital LLC | 70,354 | $164.6K | 0.02% | +10,065+16.7% | Added |
| Jane Street Group, LLC | 106,345 | $248.8K | 0.00% | −51,999−32.8% | Reduced |
| Bridgeway Capital Management, LLC | 114,800 | $268.6K | 0.01% | 00.0% | Unchanged |
| Northern Trust Corp | 120,984 | $283.1K | 0.00% | 00.0% | Unchanged |
| Marshall Wace, LLP | 157,072 | $367.5K | 0.00% | +157,072 | New |
| Squarepoint Ops LLC | 194,301 | $454.7K | 0.00% | +74,867+62.7% | Added |
| Ionic Capital Management LLC | 195,939 | $458.5K | 0.38% | 00.0% | Unchanged |
| State Street Corp | 214,751 | $502.5K | 0.00% | +4,600+2.2% | Added |
| Vanguard Fiduciary Trust Co | 264,115 | $618.0K | 0.00% | +264,115 | New |
| Gsa Capital Partners LLP | 278,304 | $651.0K | 0.04% | +99,374+55.5% | Added |
| Susquehanna International Group, LLP | 333,115 | $779.5K | 0.00% | +39,415+13.4% | Added |
| Citadel Advisors LLC | 376,458 | $880.9K | 0.00% | −21,406−5.4% | Reduced |
| Anson Funds Management LP | 421,956 | $987.4K | 0.13% | −203,106−32.5% | Reduced |
| BlackRock, Inc. | 433,202 | $1.01M | 0.00% | −414−0.1% | Reduced |
| Geode Capital Management, LLC | 519,922 | $1.22M | 0.00% | −9,273−1.8% | Reduced |
| Two Sigma Investments, LP | 885,631 | $2.07M | 0.00% | +513,061+137.7% | Added |
| Alphabet Inc. | 889,979 | $2.08M | 0.05% | 00.0% | Unchanged |
| Renaissance Technologies LLC | 1,189,235 | $2.78M | 0.00% | −90,287−7.1% | Reduced |
| Vanguard Capital Management LLC | 1,799,880 | $4.21M | 0.00% | +1,799,880 | New |
| Pfizer Inc | 2,362,348 | $5.50M | 2.31% | 00.0% | Unchanged |
| GSK plc | 9,190,606 | $21.5M | 3.59% | 00.0% | Unchanged |
| EAM Investors, LLC | 0 | $0 | 0.00% | −218,084−100.0% | Sold out |
| Two Sigma Advisers, LP | 0 | $0 | 0.00% | −216,600−100.0% | Sold out |
| SEI Investments Co | 0 | $0 | 0.00% | −132,010−100.0% | Sold out |
| ADAR1 Capital Management, LLC | 0 | $0 | 0.00% | −113,839−100.0% | Sold out |
| Axxcess Wealth Management, LLC | 0 | $0 | 0.00% | −32,548−100.0% | Sold out |
| Millennium Management LLC | 0 | $0 | 0.00% | −24,107−100.0% | Sold out |
| XTX Topco Ltd | 0 | $0 | 0.00% | −15,175−100.0% | Sold out |
| Texas Yale Capital Corp. | 0 | $0 | 0.00% | −10,000−100.0% | Sold out |
| Tower Research Capital LLC (TRC) | 0 | $0 | 0.00% | −7,215−100.0% | Sold out |
| Cullen/Frost Bankers, Inc. | 0 | $0 | 0.00% | −3,000−100.0% | Sold out |
| Bank of America Corp | 0 | $0 | 0.00% | −744−100.0% | Sold out |
| Rockefeller Capital Management L.P. | 0 | $0 | 0.00% | −200−100.0% | Sold out |
| SageView Advisory Group, LLC | 0 | $0 | 0.00% | −17−100.0% | Sold out |
| Vanguard Group Inc | – | – | – | – | Not filed |