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 49 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 · View history	$4.88M 3,750,450 shares	0.70%	0(0.00%)Unchanged	SEC filing ↗ Aug 13, 2024	▾
02	VANGUARD GROUP INC CIK 102909 · View history	$2.30M 1,770,525 shares	0.00%	+117.09K(+7.10%)Added	SEC filing ↗ Aug 13, 2024	▾
03	ACADIAN ASSET MANAGEMENT LLC CIK 916542 · View history	$1.39M 1,071,860 shares	0.00%	+309.26K(+40.60%)Added	SEC filing ↗ Aug 6, 2024	▾
04	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$1.27M 975,952 shares	0.00%	+121.49K(+14.20%)Added	SEC filing ↗ Aug 9, 2024	▾
05	ADAR1 Capital Management, LLC CIK 1940272 · View history	$1.19M 918,929 shares	0.24%	-8.00K(-0.90%)Reduced	SEC filing ↗ Aug 13, 2024	▾
06	Alphabet Inc. CIK 1652044 · View history	$1.16M 889,979 shares	0.06%	0(0.00%)Unchanged	SEC filing ↗ Aug 2, 2024	▾
07	Murchinson Ltd. CIK 1838556 · Amended · View history	$1.14M 873,910 shares	0.24%	0(0.00%)Unchanged	SEC filing ↗ Aug 15, 2024	▾
08	Atlas Venture Life Science Advisors, LLC CIK 1917529 · View history	$695.94K 535,336 shares	0.07%	-72.28K(-11.90%)Reduced	SEC filing ↗ Aug 9, 2024	▾
09	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$639.99K 492,187 shares	0.00%	+22.75K(+4.80%)Added	SEC filing ↗ Aug 9, 2024	▾
10	BlackRock Inc. CIK 1364742 · View history	$628.42K 483,402 shares	0.00%	+6.51K(+1.40%)Added	SEC filing ↗ Aug 13, 2024	▾
11	NOVO HOLDINGS A/S CIK 1388325 · Amended · View history	$609.57K 468,902 shares	0.03%	0(0.00%)Unchanged	SEC filing ↗ Aug 20, 2024	▾
12	AWM Investment Company, Inc. CIK 1535264 · View history	$433.42K 333,400 shares	0.06%	0(0.00%)Unchanged	SEC filing ↗ Aug 14, 2024	▾
13	CITADEL ADVISORS LLC CIK 1423053 · View history	$405.64K 312,034 shares	0.00%	+312.03KNew	SEC filing ↗ Aug 14, 2024	▾
14	BRIDGEWAY CAPITAL MANAGEMENT, LLC CIK 1107261 · View history	$240.24K 184,800 shares	0.01%	0(0.00%)Unchanged	SEC filing ↗ Aug 14, 2024	▾
15	STATE STREET CORP CIK 93751 · View history	$169.66K 130,511 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ Aug 14, 2024	▾
16	DAFNA Capital Management LLC CIK 1389933 · View history	$162.50K 125,000 shares	0.04%	0(0.00%)Unchanged	SEC filing ↗ Aug 14, 2024	▾
17	NORTHERN TRUST CORP CIK 73124 · View history	$145.99K 112,303 shares	0.00%	-2.26K(-2.00%)Reduced	SEC filing ↗ Aug 14, 2024	▾
18	MILLENNIUM MANAGEMENT LLC CIK 1273087 · View history	$128.07K 98,518 shares	0.00%	-49.35K(-33.40%)Reduced	SEC filing ↗ Aug 14, 2024	▾
19	Man Group plc CIK 1637460 · View history	$95.51K 73,469 shares	0.00%	-140.56K(-65.70%)Reduced	SEC filing ↗ Aug 14, 2024	▾
20	TWO SIGMA SECURITIES, LLC CIK 1450144 · View history	$88.05K 67,728 shares	0.00%	+67.73KNew	SEC filing ↗ Aug 14, 2024	▾

Showing 20 / 49 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

Cancelled or null records excluded

Disclosed shares

13,876,979

Not deduplicated across managers

Disclosed value

$18.04M

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. · Q2 2024

Explore all 49 reporting institutions.

This page includes 20 of 49 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.