MBX BIOSCIENCES INC (MBX)
Institutional ownership reported to the SEC as of Q2 2026, across 9 quarters.
Institutions report 55,478,719 shares against 48,160,096 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end. Over 100% because an adviser and a sub-adviser can both report the same shares, and both are counted.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| Frazier Life Sciences Management, L.P. | $367.2M | 6,652,013 | 8.00% | 8q | HELD |
| FMR LLC | $293.8M | 5,322,885 | 0.01% | 7q | +81.3%+$131.7M |
| WELLINGTON MANAGEMENT GROUP LLP | $274.8M | 4,977,523 | 0.05% | 8q | +55.9%+$98.6M |
| NEA Management Company, LLC | $199.5M | 3,614,486 | 12.56% | 8q | HELD |
| ORBIMED ADVISORS LLC | $189.3M | 3,428,736 | 3.51% | 8q | -5.7%-$11.5M |
| BlackRock, Inc. | $183.5M | 3,323,672 | 0.00% | 7q | +13.0%+$21.1M |
| Paradigm Biocapital Advisors LP | $138.4M | 2,508,015 | 2.59% | new | NEW |
| NVP ASSOCIATES, LLC | $117.9M | 2,136,335 | 35.93% | 8q | HELD |
| Deep Track Capital, LP | $95.6M | 1,732,569 | 1.39% | 8q | -37.2%-$56.6M |
| Polar Capital Holdings Plc | $88.8M | 1,608,514 | 0.21% | 2q | -0.8%-$754.7K |
| VANGUARD CAPITAL MANAGEMENT LLC | $81.6M | 1,477,388 | 0.00% | 2q | HELD |
| Aaron Wealth Advisors LLC | $64.5M | 1,167,799 | 3.27% | 6q | HELD |
| Driehaus Capital Management LLC | $58.3M | 1,056,579 | 0.34% | 8q | +3.8%+$2.1M |
| Kynam Capital Management, LP | $51.6M | 934,799 | 2.85% | 4q | HELD |
| Woodline Partners LP | $49.7M | 900,092 | 0.15% | 8q | HELD |
| EVENTIDE ASSET MANAGEMENT, LLC | $48.2M | 873,492 | 0.64% | 3q | -1.9%-$911.2K |
| STATE STREET CORP | $47.7M | 864,466 | 0.00% | 7q | +9.8%+$4.3M |
| PRICE T ROWE ASSOCIATES INC /MD/ | $45.0M | 814,807 | 0.00% | 8q | -20.8%-$11.8M |
| Parkman Healthcare Partners LLC | $44.2M | 800,173 | 4.52% | 7q | HELD |
| GEODE CAPITAL MANAGEMENT, LLC | $42.7M | 773,072 | 0.00% | 8q | +15.3%+$5.7M |
| BRAIDWELL LP | $39.2M | 710,880 | 1.45% | 3q | -52.4%-$43.1M |
| TCG Crossover Management, LLC | $35.9M | 650,000 | 0.86% | 8q | HELD |
| Cormorant Asset Management, LP | $30.4M | 550,000 | 1.56% | 8q | -50.9%-$31.5M |
| Soleus Capital Management, L.P. | $28.4M | 515,279 | 0.98% | 4q | +188.0%+$18.6M |
| GOLDMAN SACHS GROUP INC | $25.3M | 459,005 | 0.00% | 4q | HELD |
| MARSHALL WACE, LLP | $22.2M | 401,885 | 0.02% | 2q | +540.9%+$18.7M |
| Caption Management, LLC | $22.1M CALL+PUT | options only | 0.10% | new | OPTIONS |
| EcoR1 Capital, LLC | $21.4M | 388,500 | 1.04% | 8q | -50.0%-$21.4M |
| VANGUARD PORTFOLIO MANAGEMENT LLC | $19.1M | 346,717 | 0.00% | 2q | +18.2%+$2.9M |
| BANK OF AMERICA CORP /DE/ | $16.5M | 298,927 | 0.00% | 7q | +939.7%+$14.9M |
| Rock Springs Capital Management LP | $16.5M | 298,218 | 0.80% | 4q | +3.6%+$565.9K |
| Candriam S.C.A. | $16.0M | 289,893 | 0.07% | 2q | -1.5%-$247.1K |
| UBS Group AG | $15.1M | 272,747 | 0.00% | 7q | -21.4%-$4.1M |
| Opaleye Management Inc. | $14.4M | 260,000 | 1.30% | 6q | HELD |
| FRANKLIN RESOURCES INC | $13.9M | 252,665 | 0.00% | new | NEW |
| Schonfeld Strategic Advisors LLC | $13.7M | 248,670 | 0.05% | 7q | +100.8%+$6.9M |
| MORGAN STANLEY | $13.7M | 248,558 | 0.00% | 7q | +687.5%+$12.0M |
| NORTHERN TRUST CORP | $13.6M | 246,678 | 0.00% | 7q | +17.1%+$2.0M |
| DIMENSIONAL FUND ADVISORS LP | $12.9M | 233,700 | 0.00% | 2q | +399.9%+$10.3M |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $12.9M | 233,095 | 0.00% | 7q | +8.5%+$1.0M |
| MILLENNIUM MANAGEMENT LLC | $12.5M | 226,151 | 0.00% | 8q | -59.9%-$18.7M |
| Tetragon Partners GP Ltd | $11.2M | 203,543 | 1.77% | 4q | +39.9%+$3.2M |
| VANGUARD FIDUCIARY TRUST CO | $11.1M | 201,429 | 0.00% | 2q | +18.4%+$1.7M |
| Caligan Partners LP | $11.0M | 200,000 | 0.52% | 2q | -76.4%-$35.8M |
| D. E. Shaw & Co., Inc. | $10.1M | 182,767 | 0.00% | 3q | -36.7%-$5.9M |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | $8.4M incl. $6.9M options CALL+PUT | 26,684 | 0.00% | 6q | +181.3%+$5.4M |
| JPMORGAN CHASE & CO | $7.5M | 139,611 | 0.00% | 7q | -5.1%-$401.0K |
| KVP Capital Advisors, LP | $6.7M | 121,524 | 4.92% | 3q | HELD |
| TWO SIGMA INVESTMENTS, LP | $6.3M | 113,475 | 0.00% | 4q | -1.4%-$88.3K |
| Burkehill Global Management, LP | $5.5M | 100,000 | 0.20% | 4q | HELD |
| Nuveen, LLC | $5.5M | 98,733 | 0.00% | 6q | +20.7%+$935.1K |
| TD Asset Management Inc | $5.3M | 95,598 | 0.00% | 8q | -17.6%-$1.1M |
| Elmind Capital, LP | $5.0M | 91,000 | 1.26% | 3q | -56.9%-$6.6M |
| Bank of New York Mellon Corp | $4.9M | 88,927 | 0.00% | 7q | +10.9%+$480.5K |
| PRUDENTIAL FINANCIAL INC | $4.9M | 88,045 | 0.01% | new | NEW |
| BARCLAYS PLC | $4.8M | 87,854 | 0.00% | 8q | +642.1%+$4.2M |
| Affinity Asset Advisors, LLC | $4.1M | 75,000 | 0.19% | 4q | -50.0%-$4.1M |
| PFM Health Sciences, LP | $3.9M | 70,971 | 0.34% | 4q | -1.3%-$50.9K |
| BOOTHBAY FUND MANAGEMENT, LLC | $3.9M | 70,353 | 0.05% | 2q | -66.2%-$7.6M |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | $3.6M | 66,112 | 0.00% | 8q | -27.1%-$1.4M |
| MOORE CAPITAL MANAGEMENT, LP | $3.6M | 64,893 | 0.05% | new | NEW |
| Rhenman & Partners Asset Management AB | $3.4M | 62,000 | 0.32% | new | NEW |
| Invesco Ltd. | $2.8M | 50,678 | 0.00% | 4q | +84.1%+$1.3M |
| ALPS ADVISORS INC | $2.7M | 48,012 | 0.01% | 7q | +31.4%+$632.7K |
| PLATINUM INVESTMENT MANAGEMENT LTD | $2.4M | 43,597 | 0.59% | 8q | HELD |
| Swiss National Bank | $2.4M | 42,900 | 0.00% | 2q | -3.4%-$82.8K |
| Ensign Peak Advisors, Inc | $2.3M | 42,156 | 0.00% | new | NEW |
| ALGERT GLOBAL LLC | $2.3M | 42,070 | 0.03% | 2q | +16.8%+$334.0K |
| Creative Planning | $2.2M | 39,524 | 0.00% | 4q | +9.9%+$196.2K |
| JANE STREET GROUP, LLC | $2.1M CALL | options only | 0.00% | 4q | OPTIONS |
| RHUMBLINE ADVISERS | $2.1M | 37,196 | 0.00% | 7q | +9.8%+$183.5K |
| DEUTSCHE BANK AG\ | $1.7M | 31,693 | 0.00% | 7q | +38.1%+$482.6K |
| WELLS FARGO & COMPANY/MN | $1.6M | 28,313 | 0.00% | 7q | +163.1%+$968.8K |
| EXCHANGE TRADED CONCEPTS, LLC | $1.5M | 27,421 | 0.01% | 2q | -20.0%-$377.7K |
| CITADEL ADVISORS LLC | $1.4M CALL+PUT | options only | 0.00% | 5q | OPTIONS |
| VOYA INVESTMENT MANAGEMENT LLC | $1.4M | 26,132 | 0.00% | new | NEW |
| Universal- Beteiligungs- und Servicegesellschaft mbH | $1.4M | 25,800 | 0.00% | new | NEW |
| TEACHERS RETIREMENT SYSTEM OF THE STATE OF KENTUCKY | $1.4M | 25,377 | 0.01% | new | NEW |
| CITIGROUP INC | $1.4M | 25,122 | 0.00% | 7q | +86.1%+$641.6K |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM | $1.3M | 23,376 | 0.00% | 7q | +2.7%+$33.7K |
| AMERICAN CENTURY COMPANIES INC | $1.3M | 22,680 | 0.00% | 3q | +159.9%+$770.3K |
| AQR CAPITAL MANAGEMENT LLC | $1.2M | 22,591 | 0.00% | 5q | -17.5%-$264.7K |
| Legal & General Group Plc | $1.2M | 21,583 | 0.00% | 8q | +11.5%+$122.8K |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | $1.2M | 21,344 | 0.00% | 3q | +194.9%+$778.7K |
| Cerity Partners LLC | $1.2M | 20,997 | 0.00% | 3q | -0.8%-$9.2K |
| Vanguard Global Advisers, LLC | $1.0M | 18,969 | 0.00% | 2q | +18.3%+$162.3K |
| MetLife Investment Management, LLC | $1.0M | 18,250 | 0.00% | 5q | +13.9%+$123.2K |
| Russell Investments Group, Ltd. | $1.0M | 18,162 | 0.00% | 5q | +371.0%+$789.7K |
| Koa Wealth Management, LLC | $944.6K | 17,113 | 0.64% | 6q | -4.5%-$44.2K |
| ALLIANCEBERNSTEIN L.P. | $925.4K | 31,000 | 0.00% | 5q | +1.6%+$14.9K |
| STATE OF WISCONSIN INVESTMENT BOARD | $881.6K | 15,971 | 0.00% | 2q | -17.1%-$181.7K |
| VANGUARD ASSET MANAGEMENT, Ltd | $814.3K | 14,752 | 0.00% | 2q | HELD |
| OPTIMIZE FINANCIAL INC. | $798.1K | 14,458 | 0.29% | 2q | HELD |
| Sound Capital Solutions LLC | $798.1K | 14,458 | 0.19% | new | FIRST |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | $788.9K | 14,292 | 0.00% | 7q | +7.3%+$53.4K |
| DAFNA Capital Management LLC | $651.9K | 11,809 | 0.12% | 4q | -93.3%-$9.0M |
| HighVista Strategies LLC | $642.2K | 11,634 | 0.15% | 2q | +1.4%+$8.9K |
| NEW YORK STATE COMMON RETIREMENT FUND | $607.2K | 11,000 | 0.00% | 6q | +22.2%+$110.4K |
| Jupiter Topco LLC | $568.3K | 10,300 | 0.00% | new | FIRST |
| FRED ALGER MANAGEMENT, LLC | $545.2K | 9,877 | 0.00% | new | NEW |
Showing the largest 100 of 175 reported holders.
What the company announced
Form 8-K filings from the last 120 days, showing only the items worth a reader's attention. Earnings releases, exhibit attachments and general disclosures are filed constantly and are left out. Filed is when the SEC received it; event is the date the company says the thing happened.
| Filed | Event date | What | Source |
|---|---|---|---|
| 2026-10-22 | 2026-10-20 | Directors or officers departed or appointed | filing |
What the insiders did
Open market purchases and sales reported on Form 4 in the last 180 days. Grants, option exercises and shares surrendered to cover tax are left out: they are compensation rather than a decision to buy or sell. Where a broker filled one order in tranches the lines are summed, because it was one decision.
Officers and directors
| Date | Insider | Role | Side | Shares | Value |
|---|---|---|---|---|---|
| 2026-05-08 | Azoulay Salomon | Chief Medical Officer | Sold | 70,003 | $2.7M ×2 |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q3 2026 | 29 | $77.6M | 1,323,395 | 10 | 12 | 4 | 0.0% |
| Q2 2026 | 175 | $3.1B | 55,478,719 | 37 | 60 | 47 | 1.1% |
| Q1 2026 | 157 | $1.6B | 53,035,289 | 32 | 43 | 47 | 0.3% |
| Q4 2025 | 140 | $1.5B | 48,428,720 | 36 | 53 | 26 | 1.2% |
| Q3 2025 | 127 | $880.8M | 47,796,242 | 48 | 29 | 30 | 5.0% |
| Q2 2025 | 89 | $423.2M | 36,874,800 | 23 | 40 | 13 | 0.6% |
| Q1 2025 | 79 | $263.2M | 35,666,401 | 26 | 23 | 13 | 0.0% |
| Q4 2024 | 63 | $606.5M | 32,941,714 | 31 | 11 | 8 | 0.0% |
| Q3 2024 | 45 | $784.1M | 30,305,441 | 44 | 0 | 0 | 0.0% |