Ticker · CUSIP 55287L101

MBX

MBX BIOSCIENCES INC

Healthcare·Biotechnology

···Share

Holders (tracked)

Combined shares

7,042,944

Combined value

$222.14M

Last close

$33.77

Quarter

2025Q4

Price is +7.1% vs the avg quarter-end implied price across tracked holders.

Price · 1Y$33.77+26.15 (+343.18%)H $43.14 · L $7.62 · Avg Vol 726K

Position opened

Tracked holders · last 8 quarters

+1 vs previous quarter over the last 6.

SEC event timeline

16 events

Ken Griffin (Citadel Advisors) trimmed2026-02-17
−186,226 shares · 2025Q4
Position
D.E. Shaw & Co. opened position2026-02-17
+671,838 shares · 2025Q4
Position
Two Sigma Investments added2026-02-17
+124,984 shares · 2025Q4
Position
Steve Cohen (Point72) added2026-02-17
+52,942 shares · 2025Q4
Position
T. Rowe Price trimmed2026-02-17
−114,220 shares · 2025Q4
Position
Wellington Management trimmed2026-02-17
−1,473,375 shares · 2025Q4
Position
Izzy Englander (Millennium Mgmt) trimmed2026-02-17
−193,367 shares · 2025Q4
Position
AQR Capital Management added2026-02-17
+15,645 shares · 2025Q4
Position
Renaissance Technologies opened position2026-02-12
+32,644 shares · 2025Q4
Position
Izzy Englander (Millennium Mgmt) trimmed2025-11-14
−111,424 shares · 2025Q3
Position
Steve Cohen (Point72) trimmed2025-11-14
−346,120 shares · 2025Q3
Position
Two Sigma Investments opened position2025-11-14
+13,587 shares · 2025Q3
Position
Wellington Management added2025-11-14
+2,556,708 shares · 2025Q3
Position
AQR Capital Management trimmed2025-11-14
−2,237 shares · 2025Q3
Position
T. Rowe Price trimmed2025-11-14
−392,184 shares · 2025Q3
Position
Norges Bank (Norway SWF) opened position2025-11-12
+25,000 shares · 2024Q3
Position

Insider activity

No insider transactions in the last 30 days.

View full insider history for MBX →

Follow-the-investor returns

If you'd copied each holder of MBX…

Cost basis inferred from each manager's quarter-over-quarter position changes. Sorted by % return on the position they're still holding.

Investor	First in	Cost basis	Return	Position value today
Steve Cohen (Point72)	2024Q3	$12.83	+163.2%	$23.0M
Izzy Englander (Millennium Mgmt)	2024Q3	$17.30	+95.1%	$15.6M
Wellington Management	2024Q3	$21.15	+59.6%	$113.1M
AQR Capital Management	2025Q2	$21.44	+57.5%	$1.1M
T. Rowe Price	2024Q3	$23.32	+44.8%	$28.4M
Two Sigma Investments	2025Q1	$29.17	+15.8%	$4.7M
Ken Griffin (Citadel Advisors)	2024Q3	$31.39	+7.6%	$27.3M
Ken Griffin (Citadel Advisors)	2024Q3	$31.39	+7.6%	$27.3M
Ken Griffin (Citadel Advisors)	2024Q3	$31.39	+7.6%	$27.3M
D.E. Shaw & Co.	2025Q4	$31.54	+7.1%	$22.7M
Renaissance Technologies	2025Q4	$31.54	+7.1%	$1.1M

Who moved on this name in 2025Q4

Position changes reported for the latest quarter, grouped by direction.

New positions2

D.E. Shaw & Co.
+671,838
$21.2M
Renaissance Technologies
+32,644
$1.0M

Added to3

Two Sigma Investments
+124,984
$3.9M
Steve Cohen (Point72)
+52,942
$1.7M
AQR Capital Management
+15,645
$493K

Trimmed4

Wellington Management
−1,473,375
$46.5M
Izzy Englander (Millennium Mgmt)
−193,367
$6.1M
Ken Griffin (Citadel Advisors)
−186,226
$5.9M
T. Rowe Price
−114,220
$4K

Exited0

—

Institutional ownership over time

Distinct super-investors holding this ticker · combined dollar value, by quarter.

Quarter	Holders	Shares	Combined value	Δ holders
2024Q3	7	4,777,410	$122.1M	—
2024Q4	4	1,740,499	$32.1M	-3
2025Q1	5	4,054,192	$29.9M	+1
2025Q2	7	5,444,166	$62.1M	+2
2025Q3	10	8,244,679	$144.3M	+3
2025Q4	11	7,042,944	$222.1M	+1

Who owns MBX

11 super-investors · 2025Q4

Tracked stake

7.04M

Combined value

$222M

% of shares outstanding

—

shares-out unknown

Quarter action mix

New2Added3Trim6

#	Manager	Shares	Value	% of book	Last action	8Q trend
1	Wellington Management	3.35M	$106M	0.0%	Trim−1.47M
2	T. Rowe Price	840.5K	$27M	0.0%	Trim−114.2K
3	Ken Griffin Citadel Advisors	809.9K	$26M	0.0%	Trim−186.2K
4	Steve Cohen Point72	680.6K	$21M	0.0%	Added+52.9K
5	D.E. Shaw & Co.	671.8K	$21M	0.0%	New+671.8K	—
6	Izzy Englander Millennium Mgmt	462.0K	$15M	0.0%	Trim−193.4K
7	Two Sigma Investments	138.6K	$4M	0.0%	Added+125.0K
8	Renaissance Technologies	32.6K	$1M	0.0%	New+32.6K	—
9	AQR Capital Management	31.4K	$991K	0.0%	Added+15.6K
10	Ken Griffin Citadel Advisors	16.9K	$533K	0.0%	Trim−186.2K
11	Ken Griffin Citadel Advisors	8.6K	$271K	0.0%	Trim−186.2K

Recent moves

20 transactions

ADDAQR Capital Management
+15,645 · 2025Q4
TRIMKen Griffin (Citadel Advisors)
−186,226 · 2025Q4
NEWD.E. Shaw & Co.
+671,838 · 2025Q4
ADDTwo Sigma Investments
+124,984 · 2025Q4
ADDSteve Cohen (Point72)
+52,942 · 2025Q4
TRIMT. Rowe Price
−114,220 · 2025Q4
TRIMWellington Management
−1,473,375 · 2025Q4
TRIMIzzy Englander (Millennium Mgmt)
−193,367 · 2025Q4
NEWRenaissance Technologies
+32,644 · 2025Q4
NEWTwo Sigma Investments
+13,587 · 2025Q3
TRIMIzzy Englander (Millennium Mgmt)
−111,424 · 2025Q3
TRIMSteve Cohen (Point72)
−346,120 · 2025Q3
TRIMT. Rowe Price
−392,184 · 2025Q3
ADDWellington Management
+2,556,708 · 2025Q3
TRIMAQR Capital Management
−2,237 · 2025Q3
NEWNorges Bank (Norway SWF)
+25,000 · 2024Q3
ADDSteve Cohen (Point72)
+863,305 · 2025Q2
SOLDTwo Sigma Investments
−33,833 · 2025Q2
NEWAQR Capital Management
+18,001 · 2025Q2
ADDT. Rowe Price
+245,994 · 2025Q2

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