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.
Q1 2026 vs. Q4 2025
How the institutions holding Spero Therapeutics, Inc. changed between Q4 2025 and Q1 2026.
All holders in Q1 2026All holders in Q4 2025
| Measure | Q4 2025 | Of which not filed for Q1 2026 | Q1 2026 | Change |
|---|---|---|---|---|
| Holders | 56 | 1 | 50 | −5 |
| Shares | 21.1M | 2.08M | 20.6M | +1.61M (+8.4%) |
| Value | $49.2M | $4.85M | $48.3M | +$3.94M (+8.9%) |
1 institution that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so the changes leave them out.
New holders (8)
Institutions that held Spero Therapeutics, Inc. at the end of Q1 2026 but not at the end of Q4 2025.
| Institution | Shares | Value | % of portfolio |
|---|---|---|---|
| Vanguard Capital Management LLC | 1,799,880 | $4.21M | 0.00% |
| Vanguard Fiduciary Trust Co | 264,115 | $618.0K | 0.00% |
| Marshall Wace, LLP | 157,072 | $367.5K | 0.00% |
| Verdad Advisers, LP | 33,455 | $78.3K | 0.09% |
| Vanguard Global Advisers, LLC | 25,446 | $59.5K | 0.00% |
| Schonfeld Strategic Advisors LLC | 20,314 | $47.5K | 0.00% |
| Occudo Quantitative Strategies LP | 16,421 | $41.2K | 0.00% |
| Caitong International Asset Management Co., Ltd | 3 | $7 | 0.00% |
Sold out (13)
Institutions that held Spero Therapeutics, Inc. at the end of Q4 2025 and filed for Q1 2026 without it.
| Institution | Shares, Q4 2025 | Value, Q4 2025 |
|---|---|---|
| EAM Investors, LLC | 218,084 | $508.1K |
| Two Sigma Advisers, LP | 216,600 | $504.7K |
| SEI Investments Co | 132,010 | $307.6K |
| ADAR1 Capital Management, LLC | 113,839 | $265.2K |
| Axxcess Wealth Management, LLC | 32,548 | $75.8K |
| Millennium Management LLC | 24,107 | $56.2K |
| XTX Topco Ltd | 15,175 | $35.4K |
| Texas Yale Capital Corp. | 10,000 | $23.3K |
| Tower Research Capital LLC (TRC) | 7,215 | $16.8K |
| Cullen/Frost Bankers, Inc. | 3,000 | $6.99K |
| Bank of America Corp | 744 | $1.73K |
| Rockefeller Capital Management L.P. | 200 | $466 |
| SageView Advisory Group, LLC | 17 | $40 |
Not filed for Q1 2026 yet (1)
Institutions that held Spero Therapeutics, Inc. at the end of Q4 2025 and haven't filed a 13F for Q1 2026. Not filing isn't selling, so they aren't counted as sold out.
| Institution | Shares, Q4 2025 | Value, Q4 2025 |
|---|---|---|
| Vanguard Group Inc | 2,083,462 | $4.85M |