Company · Ownership research

Spero Therapeutics, Inc. SPRO

CIK 0001701108 · CUSIP 84833T103

Insider tradingInitial holdingsInstitutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 84833T103 (SPRO), not CUSIP 84833T953 (SPRO), CUSIP 84833T903 (SPRO), and does not merge CUSIPs.

This page lists the top 20 of 47 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	Anson Funds Management LP CIK 1491072 · Amended · View history	$5.03M 3,750,450 shares	0.68%	0(0.00%)Unchanged	SEC filing ↗ Nov 15, 2024	▾
02	VANGUARD GROUP INC CIK 102909 · View history	$2.36M 1,763,620 shares	0.00%	-6.91K(-0.40%)Reduced	SEC filing ↗ Nov 13, 2024	▾
03	ACADIAN ASSET MANAGEMENT LLC CIK 916542 · View history	$1.44M 1,071,860 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ Nov 12, 2024	▾
04	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$1.31M 974,653 shares	0.00%	-1.30K(-0.10%)Reduced	SEC filing ↗ Nov 13, 2024	▾
05	Alphabet Inc. CIK 1652044 · View history	$1.19M 889,979 shares	0.06%	0(0.00%)Unchanged	SEC filing ↗ Nov 8, 2024	▾
06	ADAR1 Capital Management, LLC CIK 1940272 · View history	$996.24K 743,459 shares	0.17%	-175.47K(-19.10%)Reduced	SEC filing ↗ Nov 14, 2024	▾
07	BlackRock, Inc. CIK 2012383 · View history	$649.66K 484,820 shares	0.00%	—	SEC filing ↗ Nov 13, 2024	▾
08	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$644.94K 481,187 shares	0.00%	-11.00K(-2.20%)Reduced	SEC filing ↗ Nov 12, 2024	▾
09	NOVO HOLDINGS A/S CIK 1388325 · View history	$628.33K 468,902 shares	0.03%	0(0.00%)Unchanged	SEC filing ↗ Oct 24, 2024	▾
10	Atlas Venture Life Science Advisors, LLC CIK 1917529 · View history	$539.87K 402,885 shares	0.05%	-132.45K(-24.70%)Reduced	SEC filing ↗ Nov 13, 2024	▾
11	AWM Investment Company, Inc. CIK 1535264 · View history	$446.76K 333,400 shares	0.05%	0(0.00%)Unchanged	SEC filing ↗ Nov 14, 2024	▾
12	BRIDGEWAY CAPITAL MANAGEMENT, LLC CIK 1107261 · View history	$247.63K 184,800 shares	0.01%	0(0.00%)Unchanged	SEC filing ↗ Nov 14, 2024	▾
13	STATE STREET CORP CIK 93751 · View history	$174.88K 130,511 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ Nov 14, 2024	▾
14	DAFNA Capital Management LLC CIK 1389933 · View history	$167.50K 125,000 shares	0.04%	0(0.00%)Unchanged	SEC filing ↗ Nov 14, 2024	▾
15	NORTHERN TRUST CORP CIK 73124 · View history	$149.41K 111,497 shares	0.00%	-806(-0.70%)Reduced	SEC filing ↗ Nov 13, 2024	▾
16	CITADEL ADVISORS LLC CIK 1423053 · View history	$109.11K 81,425 shares	0.00%	-230.61K(-73.90%)Reduced	SEC filing ↗ Nov 14, 2024	▾
17	SUSQUEHANNA INTERNATIONAL GROUP, LLP CIK 1446194 · View history	$59.25K 44,219 shares	0.00%	+21.15K(+91.60%)Added	SEC filing ↗ Nov 14, 2024	▾
18	Man Group plc CIK 1637460 · View history	$51.56K 38,481 shares	0.00%	-34.99K(-47.60%)Reduced	SEC filing ↗ Nov 14, 2024	▾
19	MILLENNIUM MANAGEMENT LLC CIK 1273087 · View history	$43.11K 32,172 shares	0.00%	-66.35K(-67.30%)Reduced	SEC filing ↗ Nov 14, 2024	▾
20	MACKENZIE FINANCIAL CORP CIK 919859 · View history	$42.75K 31,903 shares	0.00%	-826(-2.50%)Reduced	SEC filing ↗ Nov 13, 2024	▾

Showing 20 / 47 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

Cancelled or null records excluded

Disclosed shares

12,343,754

Not deduplicated across managers

Disclosed value

$16.54M

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

Spero Therapeutics, Inc. · Q3 2024

Explore all 47 reporting institutions.

This page includes 20 of 47 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.