Who owns Spero Therapeutics, Inc.?
Prices and market caps: Cboe delayed data, at least 15 minutes delayed. Not real-time. Fundamentals from company filings.
Institutional ownership of SPRO from SEC Form 13F filings across 60 reporting managers. All positions are from one synchronized reporting period — 2026-06-30 books, filed up to 45 days after quarter end — so every row is comparable.
As of the 2026-06-30 reporting period, 60 institutions disclosed 21.4M shares of Spero Therapeutics, Inc. worth $47.5M — about 37% of shares outstanding; the largest disclosed holder is GSK plc. Source: SEC Form 13F filings, parsed by EvidInvest.
60
13F holders
$47.5M
value, 2026 filers
37%
of shares outstanding (21.4M sh)
22
new positions (2026 filers)
Top institutional holders
ordered by shares owned · positions as of 2026-06-30 · % of fund = share of the manager's own book · % of co. = share of SPRO's shares outstanding
| # | Manager | Shares | Value | % of fund | % of co. | Δ shares QoQ |
|---|---|---|---|---|---|---|
| 1 | GSK plc | 9.2M | $20.3M | 3.4% | 15.9% | 0.0% |
| 2 | Pfizer Inc | 2.4M | $5.3M | 3.1% | 4.1% | 0.0% |
| 3 | VANGUARD CAPITAL MANAGEMENT LLC | 2.0M | $4.5M | 0.0% | 3.5% | +13.1% |
| 4 | RENAISSANCE TECHNOLOGIES LLC | 947,904 | $2.1M | 0.0% | 1.6% | -20.3% |
| 5 | Alphabet Inc. | 889,979 | $2.0M | 0.0% | 1.5% | 0.0% |
| 6 | SUSQUEHANNA INTERNATIONAL GROUP, LLP | 759,290 | $1.7M | 0.0% | 1.3% | +127.9% |
| 7 | BlackRock, Inc. | 594,404 | $1.3M | 0.0% | 1% | +37.2% |
| 8 | GEODE CAPITAL MANAGEMENT, LLC | 566,329 | $1.3M | 0.0% | 1% | +8.9% |
| 9 | RAYMOND JAMES FINANCIAL INCNEW | 521,705 | $1.2M | 0.0% | 0.9% | new |
| 10 | TWO SIGMA INVESTMENTS, LP | 382,814 | $846,019 | 0.0% | 0.7% | -56.8% |
| 11 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIPNEW | 332,970 | $735,864 | 0.0% | 0.6% | new |
| 12 | VANGUARD FIDUCIARY TRUST CO | 287,648 | $635,702 | 0.0% | 0.5% | +8.9% |
| 13 | GSA CAPITAL PARTNERS LLP | 285,906 | $632,000 | 0.0% | 0.5% | +2.7% |
| 14 | DIMENSIONAL FUND ADVISORS LP | 274,820 | $607,616 | 0.0% | 0.5% | +823.2% |
| 15 | GOLDMAN SACHS GROUP INCNEW | 256,985 | $567,937 | 0.0% | 0.4% | new |
| 16 | STATE STREET CORP | 214,751 | $474,600 | 0.0% | 0.4% | 0.0% |
| 17 | JANE STREET GROUP, LLC | 158,097 | $349,394 | 0.0% | 0.3% | +48.7% |
| 18 | UBS Group AG | 139,680 | $308,693 | 0.0% | 0.2% | +4542.1% |
| 19 | BRIDGEWAY CAPITAL MANAGEMENT, LLC | 114,800 | $253,708 | 0.0% | 0.2% | 0.0% |
| 20 | NORTHERN TRUST CORP | 108,274 | $239,286 | 0.0% | 0.2% | -10.5% |
| 21 | Point72 Asset Management, L.P. | 104,377 | $230,673 | 0.0% | 0.2% | +74.9% |
| 22 | Ionic Capital Management LLC | 102,698 | $226,963 | 0.0% | 0.2% | -47.6% |
| 23 | Federation des caisses Desjardins du QuebecNEW | 91,900 | $202,180 | 0.0% | 0.2% | new |
| 24 | Shay Capital LLC | 72,391 | $159,984 | 0.0% | 0.1% | +2.9% |
| 25 | Invesco Ltd. | 64,245 | $141,981 | 0.0% | 0.1% | +41.6% |
Source: SEC Form 13F-HR filings (institutional managers over $100M in US-listed positions). 13Fs disclose long positions only, up to 45 days after quarter end; each manager's latest filed quarter is shown per row and dollar values are the manager's filed marks. Aggregates labeled "2026 filers" count only managers whose latest book is a 2026 quarter. Related: valuation · options positioning · supply chain. Research, not investment advice.