InsiderSource
MBX

MBX Biosciences, Inc.

SEC CIK 1776111
$37.25 −5.0% · 90 days
90-day buys
$0
0 open-market
90-day sells
$2.71M
4 open-market
Net insider flow
−$2.71M
Net selling
Filings shown
15
Most recent

At a glance

Over the last 90 days, insiders at MBX have sold a net $2.71M of stock (0 open-market buys vs 4 sells).

Largest recent trade: Heron Patrick J, MBX's 10% owner, spent $12M of their own money on 666,666 shares at $18, growing their stake 15%.

Most active filer: Hawryluk P. Kent, with 6 transactions among the recent filings shown.

Insider transaction history

Form 4 filings for MBX, newest first
View on SEC EDGAR ↗
MBX
MBX Biosciences, Inc.
Sell Azoulay Salomon · Chief Medical Officer · Open-market sale · filed May 11, 2026 ΔOwn −79%

Azoulay Salomon sold $2.11M of MBX, trimming their stake 79%.

−$2.11M
55,000 sh @ $38
MBX
MBX Biosciences, Inc.
Sell Azoulay Salomon · Chief Medical Officer · Open-market sale · filed May 11, 2026 ΔOwn −50%

Azoulay Salomon sold $574.6K of MBX, trimming their stake 50%.

−$574.6K
15,003 sh @ $38
MBX
MBX Biosciences, Inc.
Sell Azoulay Salomon · Chief Medical Officer · Open-market sale · filed May 8, 2026 ΔOwn −1.5%

Azoulay Salomon sold $6.8K of MBX, trimming their stake 2%.

−$6.8K
231 sh @ $30
MBX
MBX Biosciences, Inc.
Sell Hawryluk P. Kent · Director, President & CEO · Open-market sale · filed May 8, 2026 ΔOwn −0.1%

Hawryluk P. Kent sold $17.9K of MBX.

−$17.9K
607 sh @ $30
MBX
MBX Biosciences, Inc.
Buy Hawryluk P. Kent · Director, President & CEO · Open-market purchase · filed Mar 16, 2026 ΔOwn +4.0%

Hawryluk P. Kent, MBX's CEO, spent $525.7K of their own money on 18,500 shares at $28, growing their stake 4%.

+$525.7K
18,500 sh @ $28
MBX
MBX Biosciences, Inc.
Buy Hawryluk P. Kent · Director, President & CEO · Open-market purchase · filed Oct 21, 2025 ΔOwn +4.5%

Hawryluk P. Kent, MBX's CEO, spent $272.8K of their own money on 20,000 shares at $14, growing their stake 4%.

+$272.8K
20,000 sh @ $14
MBX
MBX Biosciences, Inc.
Buy Hoerter Steven L. · Director · Open-market purchase · filed Oct 20, 2025 ΔOwn NEW

Hoerter Steven L., MBX's Director, spent $265K of their own money on 20,000 shares at $13, opening a brand-new position.

+$265K
20,000 sh @ $13
MBX
MBX Biosciences, Inc.
Buy Heron Patrick J · Director, 10% Owner · Open-market purchase · filed Sep 30, 2025 ΔOwn +15%

Heron Patrick J, MBX's 10% owner, spent $12M of their own money on 666,666 shares at $18, growing their stake 15%.

+$12M
666,666 sh @ $18

About MBX insider activity

This page tracks every recent Form 4 filed for MBX Biosciences, Inc. with the U.S. Securities and Exchange Commission. Form 4 is the disclosure that company insiders — officers, directors, and holders of more than 10% of the stock — must file within two business days of buying or selling shares.

The summary above nets open-market purchases against open-market sales over the trailing 90 days. Open-market trades (codes P and S) tend to carry the most signal because they reflect a deliberate choice to put money in or take it out, as opposed to routine grants, option exercises, or tax-withholding events. Use the badges on each row to tell them apart, and always confirm details against the original filing before drawing conclusions.

Frequently asked questions

How often is MBX insider data updated?

Continuously. We read from SEC EDGAR, so new Form 4 filings for MBX Biosciences, Inc. usually appear here within minutes of being accepted by the SEC.

What does "net insider flow" mean?

It is the total dollar value of open-market insider purchases minus open-market sales over the last 90 days. A positive number (green) means insiders bought more than they sold; a negative number (red) means the reverse.

Why do some rows show grants or option exercises instead of buys?

Insiders receive stock through compensation as well as buying it outright. Form 4 captures all of these. We label each transaction by its SEC code so you can focus on open-market activity if you prefer.

Is this investment advice?

No. InsiderSource presents public filing data for informational purposes only. Insider activity is one of many factors to consider and is never a recommendation to buy or sell.