MBX Biosciences, Inc. - Common Stock (MBX)

CUSIP: 55287L101

Q4 2025 13F Holders as of 31 Dec 2025

Holder snapshot 7 signals
Share change
-32,951
Put/Call ratio
365%
SEC-reported price per share
$31.54
Number of holders
138
Value change
+$34,720,034
Number of buys
91
Open additional details 1 more signal available
Number of sells
50
Security identity Names, identifiers, and filing context for this profile. 1 source field
Shares outstanding
47,785,109

Security key

55287L101

Report period

Q4 2025

Institutions

138

Top holders

10

Ownership snapshot

Top reported holders of MBX - MBX Biosciences, Inc. - Common Stock (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
Frazier Life Sciences Pub...
Disclosed value leader
Frazier Life Sciences Man...
Comparable rows
15/15
Latest evidence
06 Nov 2025
13D/G 3/4/5 13F Lead comparable stake: 12% 13D/G row: Frazier Life Sciences Public Fund, L.P. Showing 1-6 of 15 holder rows.

Quick read

Frazier Life Sciences Public Fund, L.P. leads the comparable SEC ownership view at 12%.

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 Frazier Life Sciences Public Fund, L.P.'s linked filing trail.
Comparable ownership Top 5
Frazier Life Sciences Public Fund... 12%
New Enterprise Associates 17, L.P. 8.1%
Deep Track Capital, LP 6.6%
Norwest Venture Partners XVI, LP 4.8%
Wellington Biomedical Innovation ... 4.5%

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
Frazier Life Sciences Public Fund, L.P.
13D/G
Patrick J. Heron
12%
$72,562,680
5,224,095 shares
+$9,264,602 26 Sep 2025
New Enterprise Associates 17, L.P.
13D/G 3/4/5
Edward T. Mathers · 10%+ Owner
8.1%
$63,340,795
3,619,474 shares
$0 06 Nov 2025
Deep Track Capital, LP
13F 13D/G
Company
6.6%
from 13D/G
$55,125,000
3,150,000 shares
30 Sep 2025
Norwest Venture Partners XVI, LP
13D/G
Tiba Aynechi
4.8%
$29,738,337
2,140,989 shares
$0 26 Sep 2025
Wellington Biomedical Innovation Master Investors (Cayman) II L.P.
13D/G 3/4/5
10%+ Owner
4.5%
$35,304,395
2,017,394 shares
$0 30 Sep 2025
P. Kent Hawryluk
13D/G
4.3%
$34,925,782
1,995,759 shares
$0 30 Sep 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 Q4 2025

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

Institutions
138
Shares
48,428,720
Rows available
138
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 Q4 2025 vs Q3 2025 Across Filers

Q3 2025 holders
117
Q4 2025 holders
138
Holder diff
21
Investor Q3 2025 Shares Q4 2025 Shares Share Diff Share Chg % Q3 2025 value Q4 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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