Comparable stake leader
Frazier Life Sciences Public Fund, L.P.
SEC ownership of MBX Biosciences, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001776111.
Disclosed value leader
Frazier Life Sciences Management, L.P.
Comparable rows
50/50
Latest evidence
06 Aug 2026
- Public ticker
- MBX on Nasdaq
- Parsed ownership sources
-
13D/G, 13F, and 3/4/5
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Frazier Life Sciences Public Fund, L.P.
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
50 of 50
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
Frazier Life Sciences Public Fund, L.P.
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
06 Aug 2026
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001776111
- Issuer location
- Carmel, IN
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
3 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of MBX Biosciences, Inc. (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
50/50
Latest evidence
06 Aug 2026
13D/G
13F
3/4/5
Lead comparable stake: 12%
13D/G row: Frazier Life Sciences Public Fund, L.P.
Showing 1-8 of 50 holder rows.
Quick read
Frazier Life Sciences Public Fund, L.P. leads the comparable SEC ownership view at 12%.
50 of 50 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%
FMR LLC
11%
WELLINGTON MANAGEMENT GROUP LLP
10%
New Enterprise Associates 17, L.P.
8.1%
ORBIMED ADVISORS LLC
6.4%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Frazier Life Sciences Public Fund, L.P. |
13D/G
Patrick J. Heron
|
12%
|
$323,728,813
5,243,421 shares
|
+$1,193,187 | 06 Aug 2026 |
| FMR LLC |
13D/G
13F
Company
|
11%
|
$293,826,960
5,322,885 shares
|
+$131,719,966 | 30 Jun 2026 |
| WELLINGTON MANAGEMENT GROUP LLP |
13D/G
13F
Company
|
10%
|
$274,762,754
4,977,523 shares
|
+$89,842,562 | 30 Jun 2026 |
| 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 |
| ORBIMED ADVISORS LLC |
13D/G
3/4/5
13F
Director, 10%+ Owner · Company
|
6.4%
|
$189,841,424
3,074,853 shares
|
-$34,761,719 | 06 Aug 2026 |
| BlackRock, Inc. |
13F
13D/G
Company
|
5.5%
from 13D/G
|
$183,466,695
3,323,672 shares
|
— | 30 Jun 2026 |
| Paradigm Biocapital Advisors LP |
13F
13D/G
Company
|
5.2%
from 13D/G
|
$138,442,428
2,508,015 shares
|
— | 30 Jun 2026 |
| Norwest Venture Partners XVI, LP |
13D/G
Tiba Aynechi
|
4.8%
|
$29,738,337
2,140,989 shares
|
$0 | 26 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.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to buying over the last 12 months. Net value: +$10,328,820.
Buys
$13,063,425
Insiders: 3
Sells
$2,734,604
Insiders: 2
Net
+$10,328,820
Shares: +653,955
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 725,166
Shares: 71,211
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 370 | $0 | $24,335 | -$24,335 |
| 3-6 | 18,500 | 70,841 | $525,663 | $2,710,269 | -$2,184,607 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 706,666 | 0 | $12,537,762 | $0 | +$12,537,762 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 25 reporting-owner rows connected to MBX Biosciences, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
25
Largest Forms 3/4/5 holder
Patrick J. Heron
Net 12M change
+$10,328,820
Latest report
04 Aug 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Patrick J. Heron | Director, 10%+ Owner | $93,949,920 | +$11,999,988 | +15% | Filing P/S | 04 Jun 2026 |
| Frazier Life Sciences X, L.P. | 10%+ Owner | $48,669,154 | Mixed | 16 Sep 2024 | ||
| Carmen Chang | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| Ali Behbahani | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| Rick Yang | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| New Enterprise Associates 17, L.P. | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| Forest Baskett | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| Mohamad Makhzoumi | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| Scott D. Sandell | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| Mathers Edward T. | Director | $38,638,855 | Mixed | 04 Jun 2026 | ||
| Paul Edward Walker | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| Anthony A. Florence Jr. | 10%+ Owner | $38,638,855 | Mixed | 16 Sep 2024 | ||
| P. Kent Hawryluk | President & CEO, Director | $36,025,576 | +$780,522 | +2.2% | Mixed | 06 May 2026 |
| Tiba Aynechi | Director | $22,837,421 | Mixed | 04 Jun 2026 | ||
| Wellington Biomedical Innovation Master Investors (Cayman) II L.P. | 10%+ Owner | $19,136,404 | Mixed | 16 Sep 2024 | ||
| Carl L. Gordon | Director, 10%+ Owner | $8,107,095 | Filing P/S | 14 Feb 2025 | ||
| ORBIMED ADVISORS LLC | Director, 10%+ Owner | $8,107,095 | Filing P/S | 14 Feb 2025 | ||
| Steven L. Hoerter | President and CEO, Director | $5,947,161 | +$264,984 | +4.7% | Mixed | 03 Aug 2026 |
| John W. Smither | Chief Financial Officer | $1,545,600 | Median | 03 Aug 2026 | ||
| James M. Cornelius | Director | $1,091,257 | Mixed | 05 Jun 2025 |
Recent insider transactions for MBX Biosciences, Inc.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Salomon Azoulay | MBX | Common Stock | Sale | -2.51% | $24,335 | $65.77 | -370 | 14,399 | 04 Aug 2026 | Direct |
| John W. Smither | MBX | Common Stock | Award | 28,000 | 28,000 | 03 Aug 2026 | Direct | |||
| John W. Smither | MBX | Stock option (right to buy) | Award | 130,000 | 130,000 | 03 Aug 2026 | Direct | |||
| Steven L. Hoerter | MBX | Common Stock | Award | 594.7% | 71,000 | 82,938 | 03 Aug 2026 | Direct | ||
| Steven L. Hoerter | MBX | Stock option (right to buy) | Award | 331,000 | 331,000 | 03 Aug 2026 | Direct | |||
| Mathers Edward T. | MBX | Stock option (right to buy) | Award | 12,500 | 12,500 | 04 Jun 2026 | Direct | |||
| Ora H. Pescovitz | MBX | Stock option (right to buy) | Award | 12,500 | 12,500 | 04 Jun 2026 | Direct | |||
| Patrick J. Heron | MBX | Stock option (right to buy) | Award | 12,500 | 12,500 | 04 Jun 2026 | Direct | |||
| Laurie Stelzer | MBX | Stock option (right to buy) | Award | 12,500 | 12,500 | 04 Jun 2026 | Direct | |||
| Steven L. Hoerter | MBX | Stock option (right to buy) | Award | 12,500 | 12,500 | 04 Jun 2026 | Direct | |||
| Steven Ryder | MBX | Stock option (right to buy) | Award | 12,500 | 12,500 | 04 Jun 2026 | Direct | |||
| Tiba Aynechi | MBX | Stock option (right to buy) | Award | 12,500 | 12,500 | 04 Jun 2026 | Direct | |||
| Salomon Azoulay | MBX | Common Stock | Sale | -82.6% | $2,685,515 | $38.36 | -70,003 | 14,769 | 08 May 2026 | Direct |
| Salomon Azoulay | MBX | Common Stock | Options Exercise | 70,003 | 69,769 | 08 May 2026 | Direct | |||
| Salomon Azoulay | MBX | Stock option (right to buy) | Options Exercise | 56.2% | 70,003 | 194,540 | 08 May 2026 | Direct | ||
| Salomon Azoulay | MBX | Common Stock | Sale | -1.54% | $6,824 | $29.54 | -231 | 14,769 | 06 May 2026 | Direct |
| P. Kent Hawryluk | MBX | Common Stock | Sale | -0.08% | $17,931 | $29.54 | -607 | 727,667 | 06 May 2026 | Direct |
| Steven L. Hoerter | MBX | Common Stock | Award | 11,938 | 11,938 | 01 May 2026 | Direct | |||
| Steven L. Hoerter | MBX | Stock option (right to buy) | Award | 74,249 | 74,249 | 01 May 2026 | Direct | |||
| P. Kent Hawryluk | MBX | Common Stock | Purchase | 3.95% | $525,663 | $28.41 | 18,500 | 486,777 | 13 Mar 2026 | By Trust |
| P. Kent Hawryluk | MBX | Common Stock | Options Exercise | 4.11% | 28,768 | 728,274 | 26 Feb 2026 | Direct | ||
| P. Kent Hawryluk | MBX | Stock option (right to buy) | Options Exercise | -23.9% | -28,768 | 91,668 | 26 Feb 2026 | Direct | ||
| Salomon Azoulay | MBX | Common Stock | Award | 15,000 | 15,000 | 02 Feb 2026 | Direct | |||
| Salomon Azoulay | MBX | Stock option (right to buy) | Award | 70,000 | 70,000 | 02 Feb 2026 | Direct | |||
| Richard Bartram | MBX | Common Stock | Award | 15,000 | 15,000 | 02 Feb 2026 | Direct | |||
| Richard Bartram | MBX | Stock option (right to buy) | Award | 70,000 | 70,000 | 02 Feb 2026 | Direct | |||
| P. Kent Hawryluk | MBX | Common Stock | Award | 5.31% | 35,250 | 699,506 | 02 Feb 2026 | Direct | ||
| P. Kent Hawryluk | MBX | Stock option (right to buy) | Award | 164,500 | 164,500 | 02 Feb 2026 | Direct | |||
| Laurie Stelzer | MBX | Stock option (right to buy) | Award | 32,000 | 32,000 | 20 Jan 2026 | Direct | |||
| Steven L. Hoerter | MBX | Stock option (right to buy) | Award | 0 | 0 | 22 Nov 2025 | Direct | |||
| Steven L. Hoerter | MBX | Stock option (right to buy) | Award | 33,751 | 33,751 | 06 Nov 2025 | Direct | |||
| P. Kent Hawryluk | MBX | Common Stock | Options Exercise | 38% | 182,859 | 664,256 | 24 Oct 2025 | Direct | ||
| P. Kent Hawryluk | MBX | Stock option (right to buy) | Options Exercise | -58.5% | -182,859 | 129,708 | 24 Oct 2025 | Direct | ||
| P. Kent Hawryluk | MBX | Common Stock | Purchase | 4.46% | $272,790 | $13.64 | 20,000 | 468,277 | 20 Oct 2025 | By Trust |
| Steven L. Hoerter | MBX | Common Stock | Purchase | $264,984 | $13.25 | 20,000 | 20,000 | 17 Oct 2025 | By Trust | |
| Patrick J. Heron | MBX | Common Stock | Purchase | 14.6% | $11,999,988 | $18.00 | 666,666 | 5,219,440 | 26 Sep 2025 | By Frazier Life Sciences X, L.P. |
* marks a reported price that did not pass the local price check.