Spero Therapeutics, Inc. - Common Stock, par value $0.001 per share (SPRO)

CUSIP: 84833T103

Q2 2025 13F Holders as of 30 Jun 2025

Holder snapshot 6 signals
Share change
-4,029,340
SEC-reported price per share
$2.90
Number of holders
44
Value change
-$7,947,299
Number of buys
24
Number of sells
19
Security identity Names, identifiers, and filing context for this profile. 1 source field
Shares outstanding
55,705,828

Security key

84833T103

Report period

Q2 2025

Institutions

44

Top holders

10

Ownership snapshot

Top reported holders of SPRO - Spero Therapeutics, Inc. - Common Stock, par value $0.001 per share (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Comparable stake leader
GSK plc
Disclosed value leader
GSK plc
Comparable rows
15/15
Latest evidence
30 Jun 2025
3/4/5 13D/G 13F Lead comparable stake: 16% 13D/G row: GSK plc Showing 1-6 of 15 holder rows.

Quick read

GSK plc leads the comparable SEC ownership view at 16%.

15 of 15 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.

Open SEC evidence Opens GSK plc's linked filing trail.
Comparable ownership Top 5
GSK plc 16%
Anson Funds Management LP 2.9%
PFIZER INC 4.2%
VANGUARD GROUP INC 3.2%
RENAISSANCE TECHNOLOGIES LLC 1.7%

Ownership % is shown only when SEC disclosures are safely comparable across share classes.

Detailed SEC evidence table Showing 1-6 of 15 holder rows
Holder Evidence Ownership % Position 12M Net Δ As of
GSK plc
3/4/5 13D/G
10%+ Owner
16%
from 13D/G
$11,672,070
9,190,606 shares
07 Nov 2022
Anson Funds Management LP
13D/G 13F
Company
2.9%
$4,587,932
1,615,469 shares
$0 30 Jun 2025
PFIZER INC
13F
Company
13F
4.2%
$1,700,891
2,362,348 shares
31 Mar 2025
VANGUARD GROUP INC
13F
Company
13F
3.2%
$1,269,807
1,763,620 shares
31 Mar 2025
RENAISSANCE TECHNOLOGIES LLC
13F
Company
13F
1.7%
$699,053
970,907 shares
31 Mar 2025
Alphabet Inc.
13F
Company
13F
1.6%
$640,785
889,979 shares
31 Mar 2025
How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

13F holder rows

Institutional holders as of Q2 2025

Investor-level positions for this CUSIP, loaded as an interactive table.

Institutions
44
Shares
11,078,704
Rows available
44
Investor Option Weight % Change % SEC-reported value * Price Shares Share Change Activity Report Period

* SEC-reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that did not pass the local price check.

Compare Q2 2025 vs Q1 2025 Across Filers

Q1 2025 holders
38
Q2 2025 holders
44
Holder diff
6
Investor Q1 2025 Shares Q2 2025 Shares Share Diff Share Chg % Q1 2025 value Q2 2025 value Value change Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend
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