Spero Therapeutics, Inc.

SPRO

Exchange: Nasdaq
Industry: Pharmaceutical Preparations
SEC CIK: 0001701108

SEC filings (opens in a new tab)

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 2022 vs. Q4 2021

How the institutions holding Spero Therapeutics, Inc. changed between Q4 2021 and Q1 2022.

All holders in Q1 2022 All holders in Q4 2021

13F holders of SPRO: Q4 2021 compared with Q1 2022
Measure	Q4 2021	Of which not filed for Q1 2022	Q1 2022	Change
Holders	84	1	100	+17
Shares	19.8M	110	20.2M	+451.6K (+2.3%)
Value	$316.7M	$1.00K	$176.1M	−$140.6M (−44.4%)

1 institution that held it in Q4 2021 haven't filed for Q1 2022 yet. Not filing isn't selling, so the changes leave them out.

New holders (25)

Institutions that held Spero Therapeutics, Inc. at the end of Q1 2022 but not at the end of Q4 2021.

Institutions new to SPRO in Q1 2022
Institution	Shares	Value	% of portfolio
Renaissance Technologies LLC	109,100	$949.0K	0.00%
Two Sigma Investments, LP	78,908	$686.0K	0.00%
Knoll Capital Management, LLC	70,000	$609.0K	0.38%
Millennium Management LLC	61,261	$533.0K	0.00%
Eversept Partners, LP	59,639	$518.9K	0.05%
Parametric Portfolio Associates LLC	44,168	$384.0K	0.00%
Walleye Capital LLC	40,009	$348.0K	0.01%
Marshall Wace, LLP	26,027	$227.0K	0.00%
Gsa Capital Partners LLP	25,916	$225.0K	0.03%
Trexquant Investment LP	24,151	$210.0K	0.01%
Assenagon Asset Management S.A.	23,123	$201.0K	0.00%
D. E. Shaw & Co., Inc.	18,646	$162.0K	0.00%
Two Sigma Advisers, LP	16,400	$143.0K	0.00%
Jane Street Group, LLC	15,622	$136.0K	0.00%
Cubist Systematic Strategies, LLC	14,144	$123.0K	0.00%
XTX Topco Ltd	13,260	$115.0K	0.05%
HRT Financial LP	11,277	$98.0K	0.00%
Engineers Gate Manager LP	10,957	$95.0K	0.00%
Citadel Advisors LLC	10,797	$94.0K	0.00%
Simplex Trading, LLC	6,346	$55.0K	0.00%
Amalgamated Bank	3,887	$34.0K	0.00%
Amalgamated Financial Corp.	3,887	$34.0K	0.00%
TCWP LLC	425	$3.00K	0.00%
FMR LLC	103	$1.00K	0.00%
Quadrant Capital Group LLC	106	$1.00K	0.00%

Sold out (8)

Institutions that held Spero Therapeutics, Inc. at the end of Q4 2021 and filed for Q1 2022 without it.

Institutions that sold out of SPRO in Q1 2022
Institution	Shares, Q4 2021	Value, Q4 2021
Rafferty Asset Management, LLC	34,958	$560.0K
IndexIQ Advisors LLC	28,689	$459.0K
MetLife Investment Management	9,977	$159.7K
Metropolitan Life Insurance Co	6,987	$111.9K
Brewin Dolphin Wealth Management Ltd	600	$10.0K
Geneos Wealth Management Inc.	590	$9.00K
C M Bidwell & Associates Ltd	372	$6.00K
CoreCap Advisors, LLC	142	$2.00K

Not filed for Q1 2022 yet (1)

Institutions that held Spero Therapeutics, Inc. at the end of Q4 2021 and haven't filed a 13F for Q1 2022. Not filing isn't selling, so they aren't counted as sold out.

Institutions holding SPRO in Q4 2021 that haven't filed for Q1 2022
Institution	Shares, Q4 2021	Value, Q4 2021
Carroll Financial Associates, Inc.	110	$1.00K