Spero TherapeuticsSPRO
13F holders, Q2 2026 (June 30)59holders +9
21new positions
12sold out
3famous investors
$2.21avg. 13F price*
At the end of Q2 2026, 59 institutions reported holding Spero Therapeutics Inc. (SPRO) in their 13F filings, up 9 from Q1 2026. 21 opened new positions and 12 sold out. The largest holders were GSK plc ($20.3M), Pfizer Inc ($5.3M) and Vanguard Capital Management LLC ($4.5M). 3 famous investors held it, including Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio), Steve Cohen (0.0% of Point72 Asset Management's portfolio) and Israel Englander (0.0% of Millennium Management's portfolio).
- Company
- Spero Therapeutics Inc.
- CUSIP
- 84833T103
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q1 2026 → Q2 2026
| Institutions | Total Value | |
|---|---|---|
| New Positions | 21 | $3.3M |
| Exits | 12 | $3.0M |
All 13F filers, Q1 2026 → Q2 2026: 2,942,173 shares bought and 2,162,644 shares sold, net +779,529 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 59 holders
| GSK plc | 3.37% | No change | 9,190,606 | $20.3M |
| Pfizer Inc | 3.13% | No change | 2,362,348 | $5.3M |
| Vanguard Capital Management LLC | 0.00% | Add +13.1% | 2,036,226 | $4.5M |
| Renaissance Technologies | 0.00% | Reduce -20.3% | 947,904 | $2.1M |
| Alphabet Inc. | 0.00% | No change | 889,979 | $2.0M |
| Susquehanna International Group, LLP | 0.00% | Add +127.9% | 759,290 | $1.7M |
| BlackRock, Inc. | 0.00% | Add +37.2% | 594,404 | $1.3M |
| Geode Capital Management, LLC | 0.00% | Add +8.9% | 566,329 | $1.3M |
| Raymond James Financial Inc. | 0.00% | New | 521,705 | $1.2M |
| Two Sigma Investments, LP | 0.00% | Reduce -56.8% | 382,814 | $846K |
| Arrowstreet Capital, Limited Partnership | 0.00% | New | 332,970 | $736K |
| Vanguard Fiduciary Trust Co. | 0.00% | Add +8.9% | 287,648 | $636K |
| Gsa Capital Partners LLP | 0.04% | Add +2.7% | 285,906 | $632K |
| Dimensional Fund Advisors LP | 0.00% | Add +823.2% | 274,820 | $608K |
| Goldman Sachs Group Inc. | 0.00% | New | 256,985 | $568K |
| State Street Corp. | 0.00% | No change | 214,751 | $475K |
| Jane Street Group, LLC | 0.00% | Add +48.7% | 158,097 | $349K |
| UBS Group AG | 0.00% | Add +4542.1% | 139,680 | $309K |
| Bridgeway Capital Management, LLC | 0.00% | No change | 114,800 | $254K |
| Northern Trust Corp. | 0.00% | Reduce -10.5% | 108,274 | $239K |
| Point72 Asset Management | 0.00% | Add +74.9% | 104,377 | $231K |
| Ionic Capital Management LLC | 0.24% | Reduce -47.6% | 102,698 | $227K |
| Federation des caisses Desjardins du Quebec | 0.00% | New | 91,900 | $202K |
| Shay Capital LLC | 0.02% | Add +2.9% | 72,391 | $160K |
| Invesco Ltd. | 0.00% | Add +41.6% | 64,245 | $142K |
| Simplex Trading, LLC | 0.00% | Add +102.3% | 61,312 | $135K |
| Verdad Advisers, LP | 0.11% | Add +53.4% | 51,335 | $113K |
| XTX Topco Ltd | 0.00% | New | 50,536 | $112K |
| American Century Companies Inc. | 0.00% | New | 36,811 | $81K |
| Capital Asset Advisory Services LLC | 0.00% | No change | 32,548 | $72K |
| Axxcess Wealth Management, LLC | 0.00% | New | 32,548 | $72K |
| Three Seasons Wealth, LLC | 0.01% | No change | 30,000 | $66K |
| Charles Schwab Investment Management Inc. | 0.00% | No change | 28,565 | $63K |
| Vanguard Global Advisers, LLC | 0.00% | No change | 25,446 | $56K |
| Global Retirement Partners, LLC | 0.00% | — | 25,000 | $55K |
| Oppenheimer & Co. Inc. | 0.00% | New | 22,850 | $50K |
| Millennium Management | 0.00% | New | 19,298 | $43K |
| Assenagon Asset Management S.A. | 0.00% | No change | 18,636 | $41K |
| DLK Investment Management, LLC | 0.02% | New | 31,355 | $41K |
| Susquehanna Portfolio Strategies, LLC | 0.00% | New | 17,628 | $39K |
| Susquehanna Fundamental Investments, LLC | 0.00% | New | 16,095 | $36K |
| Qube Research & Technologies Ltd | 0.00% | New | 13,644 | $30K |
| SG Americas Securities, LLC | 0.00% | New | 11,268 | $25K |
| Group One Trading LLC | 0.00% | New | 10,869 | $24K |
| Two Sigma Securities, LLC | 0.00% | New | 10,576 | $23K |
| Prudential Financial Inc. | 0.00% | New | 10,400 | $23K |
| Citigroup Inc. | 0.00% | Reduce -49.7% | 9,625 | $21K |
| FNY Investment Advisers, LLC | 0.01% | Add +56.6% | 8,300 | $18K |
| Jones Financial Companies LLLP | 0.00% | No change | 7,678 | $17K |
| Royal Bank of Canada | 0.00% | New | 2,014 | $4K |
| Morgan Stanley | 0.00% | Reduce -79.9% | 914 | $2K |
| FMR LLC | 0.00% | New | 300 | $663 |
| Osaic Holdings, Inc. | 0.00% | No change | 290 | $640 |
| JPMorgan Chase & Co. | 0.00% | No change | 236 | $533 |
| Wells Fargo & Company | 0.00% | No change | 200 | $442 |
| Rialto Wealth Management, LLC | 0.00% | New | 172 | $381 |
| US Bancorp \de | 0.00% | No change | 151 | $334 |
| SBI Securities Co., Ltd. | 0.00% | Add +44.4% | 13 | $29 |
| Farther Finance Advisors, LLC | 0.00% | No change | 10 | $22 |
"% of holder's portfolio" is SPRO's weight in each manager's 13F, not the share of Spero Therapeutics Inc. the manager owns.