Spero Therapeutics, Inc. (SPRO) — Institutional Holders, Q2 2026
61 institutional investment managers reported a SPRO position on SEC Form 13F-HR for the quarter ended June 30, 2026, with a combined reported value of $47.5M. Every filer is listed below, ranked by position value. Put and call option positions are excluded, and a firm filing several lots or share classes is shown once with its total.
SPRO in Q2 2026: what funds did
Funds that filed a 13F for both Q1 2026 and Q2 2026, by what they did with the common stock. Share counts are adjusted for any split between the two quarters; dollar figures are the change in shares at this quarter’s price.
Biggest buyers
- RAYMOND JAMES FINANCIALNew · +521,705 sh+$1.2M
- SUSQUEHANNA INTERNATIONAL GROUP, LLPAdded · +426,175 sh+$941.8K
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIPNew · +332,970 sh+$735.9K
- GOLDMAN SACHS GROUPNew · +256,985 sh+$567.9K
- DIMENSIONAL FUND ADVISORSAdded · +245,052 sh+$541.6K
Biggest sellers
- TWO SIGMA INVESTMENTSTrimmed · -502,817 sh-$1.1M
- Anson Funds ManagementSold out · -421,956 sh-$932.5K
- CITADEL ADVISORSSold out · -376,458 sh-$832.0K
- RENAISSANCE TECHNOLOGIESTrimmed · -241,331 sh-$533.3K
- Squarepoint OpsSold out · -194,301 sh-$429.4K
SPRO 13F holders ranked 1–61 of 61
| # | Institution | Shares | Value | % of portfolio | QoQShares vs Q1 2026 |
|---|---|---|---|---|---|
| 1 | GSK plc#1 · 9,190,606 sh | 9,190,606 | $20.3M | 3.37% | 0.0% |
| 2 | PFIZER#2 · 2,362,348 sh | 2,362,348 | $5.3M | 3.13% | 0.0% |
| 3 | VANGUARD CAPITAL MANAGEMENT#3 · 2,036,226 sh | 2,036,226 | $4.5M | <0.01% | +13.1% |
| 4 | RENAISSANCE TECHNOLOGIES#4 · 947,904 sh | 947,904 | $2.1M | <0.01% | -20.3% |
| 5 | Alphabet#5 · 889,979 sh | 889,979 | $2.0M | <0.01% | 0.0% |
| 6 | SUSQUEHANNA INTERNATIONAL GROUP, LLP#6 · 759,290 sh | 759,290 | $1.7M | <0.01% | +127.9% |
| 7 | BlackRock#7 · 594,404 sh | 594,404 | $1.3M | 0.00% | +37.2% |
| 8 | GEODE CAPITAL MANAGEMENT#8 · 566,329 sh | 566,329 | $1.3M | <0.01% | +8.9% |
| 9 | RAYMOND JAMES FINANCIAL#9 · 521,705 sh | 521,705 | $1.2M | <0.01% | New |
| 10 | TWO SIGMA INVESTMENTS#10 · 382,814 sh | 382,814 | $846.0K | <0.01% | -56.8% |
| 11 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIP#11 · 332,970 sh | 332,970 | $735.9K | <0.01% | New |
| 12 | VANGUARD FIDUCIARY#12 · 287,648 sh | 287,648 | $635.7K | <0.01% | +8.9% |
| 13 | GSA CAPITAL PARTNERS LLP#13 · 285,906 sh | 285,906 | $632.0K | 0.04% | +2.7% |
| 14 | DIMENSIONAL FUND ADVISORS#14 · 274,820 sh | 274,820 | $607.6K | <0.01% | +823.2% |
| 15 | GOLDMAN SACHS GROUP#15 · 256,985 sh | 256,985 | $567.9K | 0.00% | New |
| 16 | STATE STREET#16 · 214,751 sh | 214,751 | $474.6K | 0.00% | 0.0% |
| 17 | JANE STREET GROUP#17 · 158,097 sh | 158,097 | $349.4K | 0.00% | +48.7% |
| 18 | UBS Group AG#18 · 139,680 sh | 139,680 | $308.7K | 0.00% | +4542.1% |
| 19 | BRIDGEWAY CAPITAL MANAGEMENT#19 · 114,800 sh | 114,800 | $253.7K | <0.01% | 0.0% |
| 20 | NORTHERN#20 · 108,274 sh | 108,274 | $239.3K | 0.00% | -10.5% |
| 21 | Point72 Asset Management, L.P.#21 · 104,377 sh | 104,377 | $230.7K | <0.01% | +74.9% |
| 22 | Ionic Capital Management#22 · 102,698 sh | 102,698 | $227.0K | 0.03% | -47.6% |
| 23 | Federation des caisses Desjardins du Quebec#23 · 91,900 sh | 91,900 | $202.2K | <0.01% | New |
| 24 | Shay Capital#24 · 72,391 sh | 72,391 | $160.0K | 0.01% | +2.9% |
| 25 | Invesco Ltd.#25 · 64,245 sh | 64,245 | $142.0K | 0.00% | +41.6% |
| 26 | SIMPLEX TRADING#26 · 61,312 sh | 61,312 | $135.5K | <0.01% | +102.3% |
| 27 | Verdad Advisers#27 · 51,335 sh | 51,335 | $113.5K | 0.11% | +53.4% |
| 28 | XTX Topco Ltd#28 · 50,536 sh | 50,536 | $111.7K | <0.01% | New |
| 29 | AMERICAN CENTURY COMPANIES#29 · 36,811 sh | 36,811 | $81.4K | 0.00% | New |
| 30 | Capital Asset Advisory Services#30 · 32,548 sh | 32,548 | $71.9K | <0.01% | 0.0% |
| 31 | AXXCESS WEALTH MANAGEMENT#31 · 32,548 sh | 32,548 | $71.9K | — | New |
| 32 | Three Seasons Wealth#32 · 30,000 sh | 30,000 | $66.3K | <0.01% | 0.0% |
| 33 | CHARLES SCHWAB INVESTMENT MANAGEMENT#33 · 28,565 sh | 28,565 | $63.1K | 0.00% | 0.0% |
| 34 | Vanguard Global Advisers#34 · 25,446 sh | 25,446 | $56.2K | 0.00% | 0.0% |
| 35 | Global Retirement Partners#35 · 25,000 sh | 25,000 | $55.3K | <0.01% | — |
| 36 | OPPENHEIMER#36 · 22,850 sh | 22,850 | $50.5K | — | New |
| 37 | MILLENNIUM MANAGEMENT#37 · 19,298 sh | 19,298 | $42.6K | 0.00% | New |
| 38 | Assenagon Asset Management S.A.#38 · 18,636 sh | 18,636 | $41.2K | — | 0.0% |
| 39 | DLK Investment Management#39 · 31,355 sh | 31,355 | $40.8K | — | New |
| 40 | Susquehanna Portfolio Strategies#40 · 17,628 sh | 17,628 | $39.0K | <0.01% | New |
| 41 | SUSQUEHANNA FUNDAMENTAL INVESTMENTS#41 · 16,095 sh | 16,095 | $35.6K | <0.01% | New |
| 42 | Qube Research & Technologies Ltd#42 · 13,644 sh | 13,644 | $30.2K | 0.00% | New |
| 43 | SG Americas Securities#43 · 11,268 sh | 11,268 | $25.0K | 0.00% | New |
| 44 | GROUP ONE TRADING, L.P.#44 · 10,869 sh | 10,869 | $24.0K | 0.00% | New |
| 45 | TWO SIGMA SECURITIES#45 · 10,576 sh | 10,576 | $23.4K | <0.01% | New |
| 46 | PRUDENTIAL FINANCIAL#46 · 10,400 sh | 10,400 | $23.0K | 0.00% | New |
| 47 | CITIGROUP#47 · 9,625 sh | 9,625 | $21.3K | 0.00% | -49.7% |
| 48 | FNY Investment Advisers#48 · 8,300 sh | 8,300 | $18.0K | — | +56.6% |
| 49 | JONES FINANCIAL COMPANIES LLLP#49 · 7,678 sh | 7,678 | $17.4K | 0.00% | 0.0% |
| 50 | Integrated Wealth Concepts#50 · 6,000 sh | 6,000 | $13.3K | <0.01% | New |
| 51 | ROYAL BANK OF CANADA#51 · 2,014 sh | 2,014 | $4.0K | 0.00% | New |
| 52 | MORGAN STANLEY#52 · 914 sh | 914 | $2.0K | 0.00% | -79.9% |
| 53 | FMR#53 · 300 sh | 300 | $663.00 | 0.00% | New |
| 54 | OSAIC#54 · 290 sh | 290 | $640.00 | 0.00% | 0.0% |
| 55 | JPMORGAN CHASE#55 · 236 sh | 236 | $533.00 | 0.00% | 0.0% |
| 56 | WELLS FARGO & COMPANY#56 · 200 sh | 200 | $442.00 | 0.00% | 0.0% |
| 57 | Rialto Wealth Management#57 · 172 sh | 172 | $381.00 | <0.01% | New |
| 58 | US BANCORP \DE\#58 · 151 sh | 151 | $334.00 | 0.00% | 0.0% |
| 59 | SBI Securities , Ltd.#59 · 13 sh | 13 | $29.00 | — | +44.4% |
| 60 | Farther Finance Advisors#60 · 10 sh | 10 | $22.00 | — | 0.0% |
| 61 | INTERNATIONAL ASSETS INVESTMENT MANAGEMENT#61 · 0 sh | 0 | $0.00 | 0.00% | New |
Funds that sold out of SPRO in Q2 2026 (12)
Held SPRO at the end of Q1 2026 and filed a Q2 2026 13F without it. Not in the list above, because they no longer hold it. Largest prior position first.
| Institution | Shares sold | Value in Q1 2026 |
|---|---|---|
| Anson Funds Management421,956 sh | 421,956 | $987.4K |
| CITADEL ADVISORS376,458 sh | 376,458 | $880.9K |
| Squarepoint Ops194,301 sh | 194,301 | $454.7K |
| MARSHALL WACE, LLP157,072 sh | 157,072 | $367.5K |
| Quadrature Capital Ltd40,128 sh | 40,128 | $93.9K |
| OMERS ADMINISTRATION39,400 sh | 39,400 | $92.2K |
| Schonfeld Strategic Advisors20,314 sh | 20,314 | $47.5K |
| OCCUDO QUANTITATIVE STRATEGIES16,421 sh | 16,421 | $41.2K |
| INTREPID FAMILY OFFICE16,279 sh | 16,279 | $38.1K |
| Torrey Growth & Income Advisors17,025 sh | 17,025 | $37.6K |
| BNP PARIBAS FINANCIAL MARKETS40 sh | 40 | $94.00 |
| Caitong International Asset Management , Ltd3 sh | 3 | $7.00 |
Source: Form 13F-HR filings on SEC EDGAR, Q2 2026. Values are as reported by each manager at quarter end. “% of portfolio” is the position’s share of the manager’s total reported 13F value for the same quarter. “New” means the manager filed a 13F for Q1 2026 without this position; a dash means no comparison is available. Where a manager’s own filing is internally inconsistent its value is withheld and it is listed last. 13F data shows reported holdings, not recommendations.