- Type / Class
- Equity / COMMON STOCK
- Shares outstanding
- 47,245,286
- Total 13F shares
- 47,790,065
- Share change
- +10,949,133
- Total reported value
- $836,364,494
- Put/Call ratio
- 191%
- Price per share
- $17.50
- Number of holders
- 117
- Value change
- +$203,956,820
- Number of buys
- 67
- Number of sells
- 39
Quarterly Holders Quick Answers
What is CUSIP 55287L101?
CUSIP 55287L101 identifies MBX - MBX Biosciences, Inc. - COMMON STOCK in SEC institutional holdings data.
Need full ownership history?
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Related Filing Research
- Latest 13F filings for newly reported positions.
- Latest Schedule 13D/13G reports for ownership changes outside 13F cadence.
- Latest 10-Q/10-K reports for financial context tied to this issuer.
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Explore More Reporting Periods
Jump to adjacent filing periods for faster comparison and easier crawl discovery.
Recent filing periods for CUSIP 55287L101:
Top shareholders of MBX - MBX Biosciences, Inc. - COMMON STOCK (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Ownership % is shown only when it is directly reported or safely comparable across share classes.
Methodology: rows are grouped by holder and ranked by the holder's primary source value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
| Holder | Source | Role / Reporting | Ownership % | Shares | Holdings Value | 12M Net Δ | As of | Details |
|---|---|---|---|---|---|---|---|---|
| Patrick J. Heron |
3/4/5
|
Director, 10%+ Owner |
—
mixed-class rows
|
5,235,440
mixed-class rows
|
$93,949,920 | +$11,999,988 | 26 Sep 2025 | |
| Frazier Life Sciences Public Fund, L.P. |
13D/G
|
Patrick J. Heron |
12%
|
5,224,095
|
$72,562,680 | +$9,264,602 | 26 Sep 2025 | |
| Frazier Life Sciences Management, L.P. |
13F
|
Company |
13%
|
5,985,347
|
$68,292,809 | — | 30 Jun 2025 | |
| Frazier Life Sciences X, L.P. |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
4,552,774
|
$48,669,154 | — | 16 Sep 2024 | |
| ORBIMED ADVISORS LLC |
13F
3/4/5
|
Company · Director, 10%+ Owner |
8.5%
|
4,002,887
|
$45,672,941 | — | 30 Jun 2025 | |
| NEA Management Company, LLC |
13F
|
Company |
7.7%
|
3,614,486
|
$41,241,285 | — | 30 Jun 2025 | |
| Mathers Edward T. |
3/4/5
|
Director, 10%+ Owner |
—
mixed-class rows
|
3,630,486
mixed-class rows
|
$38,638,855 | — | 05 Jun 2025 | |
| Ali Behbahani |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Anthony A. Florence Jr. |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Carmen Chang |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Forest Baskett |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Mohamad Makhzoumi |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| New Enterprise Associates 17, L.P. |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Paul Edward Walker |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Rick Yang |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Scott D. Sandell |
3/4/5
|
10%+ Owner |
—
class O/S missing
|
3,614,486
|
$38,638,855 | — | 16 Sep 2024 | |
| Wellington Biomedical Innovation Master Investors (Cayman) II L.P. |
13D/G
3/4/5
|
10%+ Owner |
4.5%
|
2,017,394
|
$35,304,395 | $0 | 30 Sep 2025 | |
| P. Kent Hawryluk |
13D/G
|
— |
4.3%
|
1,995,759
|
$34,925,782 | $0 | 30 Sep 2025 | |
| Norwest Venture Partners XVI, LP |
13D/G
|
Tiba Aynechi |
4.8%
|
2,140,989
|
$29,738,337 | $0 | 26 Sep 2025 | |
| Deep Track Capital, LP |
13D/G
13F
|
Company |
6.6%
|
2,188,592
|
$28,604,897 | $0 | 30 Jun 2025 | |
| WELLINGTON MANAGEMENT GROUP LLP |
13F
|
Company |
4.8%
|
2,266,628
|
$25,862,225 | — | 30 Jun 2025 | |
| NVP Associates, LLC |
13F
|
Company |
4.5%
|
2,136,335
|
$24,375,582 | — | 30 Jun 2025 | |
| Tiba Aynechi |
3/4/5
|
Director |
—
mixed-class rows
|
2,152,335
mixed-class rows
|
$22,837,421 | — | 05 Jun 2025 | |
| DRIEHAUS CAPITAL MANAGEMENT LLC |
13F
|
Company |
3.3%
|
1,571,906
|
$17,935,447 | — | 30 Jun 2025 | |
| PRICE T ROWE ASSOCIATES INC /MD/ |
13F
|
Company |
2.9%
|
1,346,910
|
$15,369,000 | — | 30 Jun 2025 | |
| MPM BioImpact LLC |
13F
|
Company |
2.7%
|
1,294,416
|
$14,769,287 | — | 30 Jun 2025 | |
| EcoR1 Capital, LLC |
13F
|
Company |
2.4%
|
1,149,794
|
$13,119,150 | — | 30 Jun 2025 | |
| VANGUARD GROUP INC |
13F
|
Company |
2.2%
|
1,043,684
|
$11,908,434 | — | 30 Jun 2025 | |
| BlackRock, Inc. |
13F
|
Company |
2.1%
|
1,011,546
|
$11,541,739 | — | 30 Jun 2025 | |
| Point72 Asset Management, L.P. |
13F
|
Company |
2.1%
|
973,787
|
$11,110,910 | — | 30 Jun 2025 | |
| Woodline Partners LP |
13F
|
Company |
1.9%
|
901,103
|
$10,281,585 | — | 30 Jun 2025 | |
| Parkman Healthcare Partners LLC |
13F
|
Company |
1.8%
|
871,933
|
$9,948,756 | — | 30 Jun 2025 | |
| MILLENNIUM MANAGEMENT LLC |
13F
|
Company |
1.6%
|
766,840
|
$8,749,644 | — | 30 Jun 2025 | |
| Carl L. Gordon |
3/4/5
|
Director, 10%+ Owner |
—
mixed-class rows
|
763,850
mixed-class rows
|
$8,107,095 | — | 14 Feb 2025 | |
| Cormorant Asset Management, LP |
13F
|
Company |
1.5%
|
700,000
|
$7,987,000 | — | 30 Jun 2025 | |
| TCG Crossover Management, LLC |
13F
|
Company |
1.4%
|
650,000
|
$7,416,500 | — | 30 Jun 2025 | |
| Schonfeld Strategic Advisors LLC |
13F
|
Company |
1.3%
|
631,413
|
$7,204,420 | — | 30 Jun 2025 | |
| FRANKLIN RESOURCES INC |
13F
|
Company |
1%
|
494,852
|
$5,646,261 | — | 30 Jun 2025 | |
| RA CAPITAL MANAGEMENT, L.P. |
13F
|
Company |
0.8%
|
377,841
|
$4,311,166 | — | 30 Jun 2025 | |
| GEODE CAPITAL MANAGEMENT, LLC |
13F
|
Company |
0.74%
|
348,447
|
$3,976,287 | — | 30 Jun 2025 | |
| STATE STREET CORP |
13F
|
Company |
0.56%
|
265,119
|
$3,025,008 | — | 30 Jun 2025 | |
| Sio Capital Management, LLC |
13F
|
Company |
0.51%
|
241,000
|
$2,749,810 | — | 30 Jun 2025 | |
| Opaleye Management Inc. |
13F
|
Company |
0.51%
|
239,319
|
$2,730,630 | — | 30 Jun 2025 | |
| SECTORAL ASSET MANAGEMENT INC |
13F
|
Company |
0.41%
|
191,825
|
$2,188,723 | — | 30 Jun 2025 | |
| TD ASSET MANAGEMENT INC |
13F
|
Company |
0.36%
|
171,304
|
$1,954,579 | — | 30 Jun 2025 | |
| STEMPOINT CAPITAL LP |
13F
|
Company |
0.3%
|
141,021
|
$1,609,050 | — | 30 Jun 2025 | |
| NORTHERN TRUST CORP |
13F
|
Company |
0.24%
|
115,594
|
$1,318,927 | — | 30 Jun 2025 | |
| PLATINUM INVESTMENT MANAGEMENT LTD |
13F
|
Company |
0.24%
|
112,743
|
$1,286,398 | — | 30 Jun 2025 | |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC |
13F
|
Company |
0.23%
|
107,483
|
$1,226,381 | — | 30 Jun 2025 | |
| James M. Cornelius |
3/4/5
|
Director |
—
mixed-class rows
|
118,082
mixed-class rows
|
$1,091,257 | — | 05 Jun 2025 |
Institutional Holders of MBX Biosciences, Inc. - COMMON STOCK (MBX) as of Q3 2025
As of 30 Sep 2025,
MBX Biosciences, Inc. - COMMON STOCK (MBX) was held by
117 institutional
shareholders
that filed Form 13F with the SEC.
Together, they reported ownership of
47,790,065 shares.
The largest 10 holders included
Frazier Life Sciences Management, L.P., WELLINGTON MANAGEMENT GROUP LLP, ORBIMED ADVISORS LLC, NEA Management Company, LLC, Deep Track Capital, LP, NVP ASSOCIATES, LLC, EcoR1 Capital, LLC, Kynam Capital Management, LP, BlackRock, Inc., and VANGUARD GROUP INC.
This page lists
117
institutional shareholders reporting positions in this security
for the Q3 2025 filing period.
| Investor | Option | Weight % | Change % | Value $ | * Price | Shares | Share Change | Activity | Report Period |
|---|
Compare Q3 2025 vs Q2 2025 Across Filers
Q2 2025 holders
87
Q3 2025 holders
117
Holder diff
30
| Investor | Q2 2025 Shares | Q3 2025 Shares | Share Diff | Share Chg % | Q2 2025 Value $ | Q3 2025 Value $ | Value Diff $ | Value Chg % |
|---|
Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).
Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend
* Reported Price is the price of the security as of the portfolio date. This value is significant in that it is the last known price at which the security was still held.
An asterisk sign (*) next to the price indicates that the price is likely invalid.
An asterisk sign (*) next to the price indicates that the price is likely invalid.