ASMB · Assembly Biosciences, Inc. · Holdings
Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.
Institutional Ownership Trend
Holder Concentration
Across 93 13F filersWho Holds ASMB
Last 8 quarters through Sep 30, 2026 (filing window open)Each kind of 13F filer's share of the common shares 13F filers report. Holder type comes from regulatory records, never the filer's name; style, turnover and horizon are measured from each filer's own 13F book. The quarter selector does not change this card.
Jun 30, 2026, the newest closed quarter: 92 filers, like-for-like change +36.5%; actively managed books +28.6%; index-like books +129.4%.
| Holder type | Share | Filers | Change |
|---|---|---|---|
| Registered adviser | 54.6% | 43 | +54.2% |
| Exempt adviser | 0.4% | 4 | -65.6% |
| Adviser | 1.9% | 3 | +12.4% |
| Bank | 2.3% | 10 | +121.8% |
| Benefit plan | 0.0% | 1 | -98.3% |
| Non-US | 0.2% | 3 | +389.3% |
| Holding company | 6.2% | 6 | +287.5% |
| Unknown | 34.3% | 22 | +6.0% |
| Style | Share | Filers | Change |
|---|---|---|---|
| Index-like | 13.0% | 17 | +129.4% |
| Systematic-like | 6.8% | 12 | +57.2% |
| Concentrated | 53.9% | 12 | +25.7% |
| Diversified active | 26.3% | 51 | +28.5% |
| Not measured | 0.0% | 0 | — |
| Unknown | 0.0% | 0 | — |
| Turnover | Share | Filers | Change |
|---|---|---|---|
| Low turnover | 45.2% | 40 | +34.9% |
| Medium turnover | 31.8% | 20 | +37.2% |
| High turnover | 10.3% | 24 | +32.0% |
| Unknown | 12.8% | 8 | +45.7% |
| Not measured | 0.0% | 0 | — |
| Holding horizon | Share | Filers | Change |
|---|---|---|---|
| Short horizon | 15.5% | 19 | +41.9% |
| Medium horizon | 49.0% | 16 | +36.0% |
| Long horizon | 25.2% | 46 | +30.6% |
| Unknown | 10.2% | 11 | +47.8% |
| Not measured | 0.0% | 0 | — |
| 13F book size | Share | Filers | Change |
|---|---|---|---|
| Under $1B | 11.8% | 18 | +75.7% |
| $1B to $10B | 44.4% | 16 | +29.4% |
| $10B to $100B | 21.6% | 18 | +19.8% |
| $100B or more | 22.2% | 40 | +58.6% |
| Not measured | 0.0% | 0 | — |
| Client base | Share | Filers | Change |
|---|---|---|---|
| Individuals and high net worth | 0.1% | 3 | +1.5% |
| Pooled investment vehicles | 44.8% | 24 | +43.0% |
| Registered funds and BDCs | 5.2% | 6 | +51.4% |
| Insurance companies | 0.0% | 2 | new |
| Governments and sovereign funds | 0.4% | 3 | +193.6% |
| Other investment advisers | 0.0% | 0 | — |
| Diversified | 0.9% | 3 | +699.4% |
| Unknown | 48.6% | 51 | +27.1% |
| Private funds | Share | Filers | Change |
|---|---|---|---|
| Hedge funds | 41.8% | 30 | +52.6% |
| Private equity funds | 0.0% | 1 | new |
| Venture capital funds | 5.4% | 1 | 0.0% |
| Real estate funds | 0.0% | 1 | 0.0% |
| Other private funds | 0.1% | 2 | +10317.4% |
| Mixed private funds | 0.0% | 0 | — |
| No private funds | 5.4% | 11 | +50.0% |
| Unknown | 47.3% | 46 | +28.1% |
| Location | Share | Filers | Change |
|---|---|---|---|
| United States | 97.4% | 75 | +36.6% |
| Outside the US | 2.6% | 17 | +34.0% |
The Sep 30, 2026 filing window is still open, so its bar carries the Jun 30, 2026 positions of filers that have not filed yet.
How the mix is measured
Shares are 13F common shares restated to today's split basis; options and principal amounts are left out. The change compares only filers with a 13F in both quarters and keeps each filer in its bucket of the later quarter on both sides; a filer that continues under a new CIK is compared through its successor. Holder type comes from each filer's current regulatory profile; client base and private funds come from the Form ADV roster current at each quarter end (rosters from December 2019, so an earlier quarter reads Unknown). Style, turnover, horizon and book size are measured from each filer's 13F book in the newest measured quarter, and Not measured means none was. Actively managed books are those measured systematic-like, concentrated or diversified active.
Excluded 1 holder with no observed 2026-03-31 13F. Compared across CIK changes: JANUS HENDERSON GROUP PLC continues as Jupiter Topco LLC.
Conviction and Crowding
92 13F filers, quarter ended Jun 30, 2026Measured across every 13F filer's common-share book once the quarter's filing window closed. Crowding counts filers with high turnover or that advise private funds on Form ADV.
Managers in the top fifth by current three-year FundScore alpha were net sellers of $3,710,802 (0 buying, 1 selling).
Estimated Holder Cost Basis
Quarter ended Jun 30, 2026, on that quarter's share basisEstimated, never filed: each 13F buy is costed at its quarter's average traded price and each sale keeps the average cost, so this is what holders paid on average if they traded evenly through each quarter.
Estimated cost covers 56.7% of the 13F shares; positions already held when a filer's 13F history starts, or bought in a quarter without a trusted average price, have no estimate.
Shared Holders
Companies ASMB's active holders also own, quarter ended Jun 30, 2026| # | Company | Shared holders |
|---|---|---|
| 1 | AVTX Avalo Therapeutics, Inc. | 9 |
| 2 | SABS SAB Biotherapeutics, Inc. | 6 |
| 3 | TYRA Tyra Biosciences, Inc. | 6 |
| 4 | NERV Minerva Neurosciences, Inc. | 4 |
| 5 | DMRA Damora Therapeutics, Inc. | 6 |
| 6 | PALI Palisade Bio, Inc. | 6 |
| 7 | OVID Ovid Therapeutics Inc. | 5 |
| 8 | CLYM Climb Bio, Inc. | 5 |
| 9 | IVA Inventiva S.A. | 6 |
| 10 | CCCC C4 Therapeutics, Inc. | 5 |
Shareholder Targets
13F filers that own its peers but not ASMB, quarter ended Jun 30, 2026Found through its holder-overlap peers: AVTX, SABS, TYRA, NERV, DMRA, PALI, OVID, CLYM, IVA, CCCC, ERAS, AMLX, CUE, IFRX, TNGX, RLMD, ELVN, EWTX, EYPT, HLXC. 551 filers in all.
| # | Filer | In peers | Largest peers |
|---|---|---|---|
| 1 | ORBIMED ADVISORS LLC Registered adviser, Diversified active | $1,037,369,106 9 held | EWTX, ELVN, RLMD |
| 2 | RTW INVESTMENTS, LP Registered adviser, Diversified active | $766,551,914 3 held | TNGX, ERAS, AVTX |
| 3 | Siren, L.L.C. Unknown, Diversified active | $698,753,923 8 held | ERAS, TNGX, EWTX |
| 4 | TCG Crossover Management, LLC Unknown, Diversified active | $588,026,004 5 held | TNGX, AMLX, TYRA |
| 5 | ADAGE CAPITAL PARTNERS GP, L.L.C. Registered adviser, Diversified active | $520,585,698 16 held | TNGX, EYPT, ELVN |
| 6 | PERCEPTIVE ADVISORS LLC Registered adviser, Diversified active | $512,302,075 7 held | EWTX, AMLX, TNGX |
| 7 | Venrock Adviser, LLC Registered adviser, Concentrated | $495,581,388 4 held | ERAS, DMRA, RLMD |
| 8 | Frazier Life Sciences Management, L.P. Registered adviser, Concentrated | $457,545,444 1 held | ERAS |
| 9 | Cormorant Asset Management, LP Registered adviser, Diversified active | $431,121,440 9 held | ERAS, EWTX, EYPT |
| 10 | T. Rowe Price Investment Management, Inc. Adviser, Diversified active | $411,275,715 3 held | ERAS, ELVN, TNGX |
Fund Ownership of ASMB by Fund Type
Registered funds' Form N-PORT reports for the quarter ended Jun 30, 2026Index funds and index ETFs hold 5.56% of shares outstanding.
| Fund type | Of shares outstanding | Shares |
|---|---|---|
| Index funds | 1.01% | 206,439 |
| Index ETFs | 4.55% | 925,647 |
| Active ETFs | 0.00% | 0 |
| Active funds | 1.29% | 263,282 |
| Unclassified | 0.15% | 29,720 |
| All registered funds | 7.00% | 1,425,088 |
How fund types are measured
Each fund series counts once, with its latest Form N-PORT report dated inside the quarter; only long share positions count, restated to today's split basis. The fund type is the series' latest Form N-CEN answer on or before the quarter end (the index-fund box and the exchange-traded flag), never its name. Unclassified funds have no usable N-CEN; unit investment trusts are among them, so index ownership is a floor. Funds sit inside their advisers' 13F reports, so these shares overlap the 13F figures and are never added to them.
| Holder | Value (USD) | % of 13F | Shares | Type | Filed | Open |
|---|---|---|---|---|---|---|
| Mid GILEAD SCIENCES, INC. | $136,770,405 | 26.50% | 4,977,089 | Shares | 2026-08-03 | |
| Large FARALLON CAPITAL MANAGEMENT LLC Registered adviser | $44,094,133 | 8.54% | 1,604,590 | Shares | 2026-08-14 | |
| Mid Paradigm Biocapital Advisors LP Registered adviser | $42,696,995 | 8.27% | 1,553,748 | Shares | 2026-08-14 | |
| Mid Commodore Capital LP Registered adviser | $38,884,200 | 7.53% | 1,415,000 | Shares | 2026-08-14 | |
| Large RA CAPITAL MANAGEMENT, L.P. Registered adviser | $28,040,866 | 5.43% | 1,020,410 | Shares | 2026-08-14 | |
| Mega Jupiter Topco LLC | $23,339,011 | 4.52% | 849,309 | Shares | 2026-08-14 | |
| Mega BlackRock, Inc. Holding company | $21,072,183 | 4.08% | 766,819 | Shares | 2026-08-07 | |
| Small Parkman Healthcare Partners LLC Registered adviser | $19,818,053 | 3.84% | 721,181 | Shares | 2026-08-14 | |
| Mega VANGUARD CAPITAL MANAGEMENT LLC Registered adviser | $15,359,726 | 2.98% | 558,942 | Shares | 2026-08-13 | |
| Large Point72 Asset Management, L.P. Registered adviser | $12,657,095 | 2.45% | 460,593 | Shares | 2026-08-14 | |
| Small Seven Fleet Capital Management LP Registered adviser | $11,902,879 | 2.31% | 433,147 | Shares | 2026-08-17 | |
| Mega MILLENNIUM MANAGEMENT LLC Registered adviser | $8,211,216 | 1.59% | 298,807 | Shares | 2026-08-14 | |
| Mega GEODE CAPITAL MANAGEMENT, LLC Registered adviser | $7,706,051 | 1.49% | 280,424 | Shares | 2026-08-12 | |
| Large Schonfeld Strategic Advisors LLC Registered adviser | $6,654,364 | 1.29% | 242,153 | Shares | 2026-08-14 | |
| Mega AMERIPRISE FINANCIAL INC Adviser | $6,320,400 | 1.22% | 230,000 | Shares | 2026-08-14 | |
| Small DV EQUITIES, LLC | $6,221,884 | 1.21% | 226,415 | Shares | 2026-08-14 | |
| Large Aberdeen Group plc Holding company | $5,689,651 | 1.10% | 207,047 | Shares | 2026-07-31 | |
| Mid Affinity Asset Advisors, LLC Registered adviser | $5,221,200 | 1.01% | 190,000 | Shares | 2026-08-13 | |
| Small B Group, Inc. | $4,828,400 | 0.94% | 175,706 | Shares | 2026-08-14 | |
| Mega STATE STREET CORP Bank | $4,724,663 | 0.92% | 171,931 | Shares | 2026-09-22 | |
| Small STEMPOINT CAPITAL LP Registered adviser | $4,681,987 | 0.91% | 170,378 | Shares | 2026-08-14 | |
| Small Squadron Capital Management LLC Registered adviser | $4,396,800 | 0.85% | 160,000 | Shares | 2026-08-14 | |
| Large Woodline Partners LP Registered adviser | $4,143,434 | 0.80% | 150,780 | Shares | 2026-08-14 | |
| Large Driehaus Capital Management LLC Registered adviser | $4,122,000 | 0.80% | 150,000 | Shares | 2026-08-14 | |
| Small Ally Bridge Group (NY) LLC Registered adviser | $3,847,200 | 0.75% | 140,000 | Shares | 2026-08-14 | |
| Mega GOLDMAN SACHS GROUP INC Holding company | $3,787,650 | 0.73% | 137,833 | Shares | 2026-08-14 | |
| Mega NORTHERN TRUST CORP Bank | $3,380,836 | 0.66% | 123,029 | Shares | 2026-08-13 | |
| Mega FRANKLIN RESOURCES INC Adviser | $3,110,736 | 0.60% | 113,200 | Shares | 2026-08-13 | |
| Mega CITADEL ADVISORS LLC Registered adviser | $2,635,524 | 0.51% | 95,907 | Shares | 2026-09-02 | |
| Mega VANGUARD PORTFOLIO MANAGEMENT LLC Registered adviser | $2,504,884 | 0.49% | 91,153 | Shares | 2026-08-13 | |
| Mega VANGUARD FIDUCIARY TRUST CO | $2,032,695 | 0.39% | 73,970 | Shares | 2026-08-13 | |
| Small HighVista Strategies LLC Registered adviser | $2,017,169 | 0.39% | 73,405 | Shares | 2026-08-14 | |
| Mega Qube Research & Technologies Ltd Exempt adviser | $1,414,890 | 0.27% | 51,488 | Shares | 2026-08-14 | |
| Small MONIMUS CAPITAL MANAGEMENT, LP Registered adviser | $1,307,498 | 0.25% | 47,580 | Shares | 2026-08-14 | |
| Mega JPMORGAN CHASE & CO Bank | $1,274,658 | 0.25% | 46,385 | Shares | 2026-08-12 | |
| Large Trexquant Investment LP Registered adviser | $1,254,764 | 0.24% | 45,661 | Shares | 2026-08-14 | |
| Mega MORGAN STANLEY Holding company | $1,242,616 | 0.24% | 45,219 | Shares | 2026-08-13 | |
| Mid GSA CAPITAL PARTNERS LLP Registered adviser | $1,179,743 | 0.23% | 42,931 | Shares | 2026-08-06 | |
| Mid XTX Topco Ltd | $1,179,386 | 0.23% | 42,918 | Shares | 2026-08-14 | |
| Mega UBS Group AG Bank | $1,148,828 | 0.22% | 41,806 | Shares | 2026-08-13 | |
| Large RENAISSANCE TECHNOLOGIES LLC Registered adviser | $1,083,838 | 0.21% | 39,441 | Shares | 2026-08-13 | |
| Large Squarepoint Ops LLC Registered adviser | $940,200 | 0.18% | 34,214 | Shares | 2026-08-14 | |
| Mega CHARLES SCHWAB INVESTMENT MANAGEMENT INC Registered adviser | $800,437 | 0.16% | 29,128 | Shares | 2026-08-14 | |
| Mega BNP PARIBAS ARBITRAGE, SA Non-US | $665,098 | 0.13% | 24,203 | Shares | 2026-08-13 | |
| Mega Bank of New York Mellon Corp Bank | $659,930 | 0.13% | 24,015 | Shares | 2026-08-06 | |
| Large Connor, Clark & Lunn Investment Management Ltd. Registered adviser | $653,062 | 0.13% | 23,765 | Shares | 2026-08-13 | |
| Large Caption Management, LLC Registered adviser | $627,340 | 0.12% | 22,829 | Shares | 2026-08-14 | |
| Mid ADAR1 Capital Management, LLC Registered adviser | $561,883 | 0.11% | 20,447 | Shares | 2026-08-14 | |
| Small Palumbo Wealth Management LLC Registered adviser | $545,890 | 0.11% | 19,865 | Shares | 2026-08-12 | |
| Mega CITADEL ADVISORS LLC Registered adviser | $508,380 | 0.10% | 18,500 | Call | 2026-09-02 | |
| Mega SUSQUEHANNA INTERNATIONAL GROUP, LLP | $502,884 | 0.10% | 18,300 | Put | 2026-08-14 | |
| Mega TWO SIGMA INVESTMENTS, LP Registered adviser | $490,737 | 0.10% | 17,858 | Shares | 2026-08-14 | |
| Mid Engineers Gate Manager LP | $488,209 | 0.09% | 17,766 | Shares | 2026-08-14 | |
| Mega MARSHALL WACE, LLP Exempt adviser | $487,357 | 0.09% | 17,735 | Shares | 2026-08-13 | |
| Mega Nuveen, LLC | $463,724 | 0.09% | 16,875 | Shares | 2026-08-11 | |
| Mid Eversept Partners, LP Registered adviser | $453,694 | 0.09% | 16,510 | Shares | 2026-08-14 | |
| Mid Susquehanna Portfolio Strategies, LLC | $415,744 | 0.08% | 15,129 | Shares | 2026-08-14 | |
| Small Virtus Investment Advisers, LLC Registered adviser | $391,617 | 0.08% | 14,251 | Shares | 2026-08-11 | |
| Mega AMERICAN CENTURY COMPANIES INC | $363,807 | 0.07% | 13,239 | Shares | 2026-08-12 | |
| Mega Invesco Ltd. Adviser | $326,021 | 0.06% | 11,864 | Shares | 2026-08-14 | |
| Mega RHUMBLINE ADVISERS Registered adviser | $318,493 | 0.06% | 11,590 | Shares | 2026-08-12 | |
| Small Integrated Quantitative Investments LLC Registered adviser | $276,943 | 0.05% | 10,078 | Shares | 2026-08-14 | |
| Mega DEUTSCHE BANK AG\ Non-US | $264,220 | 0.05% | 9,615 | Shares | 2026-08-07 | |
| Mega BANK OF AMERICA CORP /DE/ Bank | $262,901 | 0.05% | 9,567 | Shares | 2026-08-14 | |
| Mega SUSQUEHANNA INTERNATIONAL GROUP, LLP | $239,076 | 0.05% | 8,700 | Call | 2026-08-14 | |
| Mega CANADA PENSION PLAN INVESTMENT BOARD Non-US | $233,580 | 0.05% | 8,500 | Shares | 2026-08-14 | |
| Small EntryPoint Capital, LLC Registered adviser | $227,671 | 0.04% | 8,285 | Shares | 2026-08-13 | |
| Mega WELLS FARGO & COMPANY/MN Bank | $226,792 | 0.04% | 8,253 | Shares | 2026-08-14 | |
| Mega PRICE T ROWE ASSOCIATES INC /MD/ Registered adviser | $225,418 | 0.04% | 8,203 | Shares | 2026-08-14 | |
| Large Brevan Howard Capital Management LP Exempt adviser | $213,382 | 0.04% | 7,765 | Shares | 2026-08-14 | |
| Small Persistent Asset Partners Ltd Exempt adviser | $190,766 | 0.04% | 6,942 | Shares | 2026-08-07 | |
| Mega BARCLAYS PLC Bank | $168,533 | 0.03% | 6,133 | Shares | 2026-08-14 | |
| Large MetLife Investment Management, LLC Registered adviser | $161,719 | 0.03% | 5,885 | Shares | 2026-08-14 | |
| Mega Vanguard Global Advisers, LLC Registered adviser | $126,820 | 0.02% | 4,615 | Shares | 2026-08-13 | |
| Mega CITIGROUP INC Bank | $125,143 | 0.02% | 4,554 | Shares | 2026-08-03 | |
| Large MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | $124,182 | 0.02% | 4,519 | Shares | 2026-08-14 | |
| Large NEW YORK STATE COMMON RETIREMENT FUND | $115,416 | 0.02% | 4,200 | Shares | 2026-07-29 | |
| Large Police & Firemen's Retirement System of New Jersey | $79,884 | 0.02% | 2,907 | Shares | 2026-07-23 | |
| Mega Legal & General Group Plc | $26,325 | 0.01% | 958 | Shares | 2026-08-14 | |
| Mid Ameritas Investment Partners, Inc. Registered adviser | $24,594 | 0.00% | 895 | Shares | 2026-08-13 | |
| Mid State of Alaska, Department of Revenue | $23,231 | 0.00% | 989 | Shares | 2026-10-15 | |
| Mega Russell Investments Group, Ltd. | $21,654 | 0.00% | 788 | Shares | 2026-08-06 | |
| Mega HSBC HOLDINGS PLC | $17,104 | 0.00% | 16,935 | Shares | 2026-08-14 | |
| Mid Tower Research Capital LLC (TRC) | $14,564 | 0.00% | 530 | Shares | 2026-08-11 | |
| Mega ROYAL BANK OF CANADA Bank | $12,091 | 0.00% | 440 | Shares | 2026-08-14 | |
| Mega NORTHWESTERN MUTUAL WEALTH MANAGEMENT CO | $7,144 | 0.00% | 260 | Shares | 2026-08-12 | |
| Mid Sterling Capital Management LLC Registered adviser | $6,107 | 0.00% | 260 | Shares | 2026-10-22 | |
| Small Accent Capital Management, LLC Registered adviser | $5,825 | 0.00% | 212 | Shares | 2026-08-12 | |
| Small Truvestments Capital LLC | $5,303 | 0.00% | 193 | Shares | 2026-08-12 | |
| Mega FMR LLC Holding company | $4,891 | 0.00% | 178 | Shares | 2026-08-13 | |
| Mega CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM Benefit plan | $3,737 | 0.00% | 136 | Shares | 2026-08-24 | |
| Large OSAIC HOLDINGS, INC. Holding company | $2,748 | 0.00% | 100 | Shares | 2026-08-14 | |
| Small Caitong International Asset Management Co., Ltd | $2,061 | 0.00% | 75 | Shares | 2026-08-05 | |
| Mid Quarry LP | $2,061 | 0.00% | 75 | Shares | 2026-08-14 | |
| Mid EverSource Wealth Advisors, LLC Registered adviser | $1,511 | 0.00% | 55 | Shares | 2026-07-24 | |
| Mid Parkside Financial Bank & Trust | $1,268 | 0.00% | 54 | Shares | 2026-10-27 | |
| Mid GAMMA Investing LLC Registered adviser | $469 | 0.00% | 20 | Shares | 2026-10-08 | |
| Large Allworth Financial LP | $274 | 0.00% | 10 | Shares | 2026-08-11 | |
| Mid Root Financial Partners, LLC Registered adviser | $23 | 0.00% | 1 | Shares | 2026-10-21 |