Who owns LBRX (LBRX)
Which tracked institutional funds hold LBRX, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See LBRX company fundamentals →
Ownership as of the 2026-Q1 13F filings. 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
The tracked-fund tape on LBRX is one-sided between 2025-Q4 and 2026-Q1: 36 added or opened and 10 trimmed or exited — on balance accumulating.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
LBRX’s largest tracked holder by dollar value, Deep Track Capital, LP, sizes it at 1.7% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 1.7pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in LBRX divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2025-Q4 and 2026-Q1, across 77 tracked filers holding LBRX, 51 increased or opened the position and 26 reduced or closed it; over the same quarter, open-market insider Form 4s were net purchases.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in LBRX between the 2025-Q4 and 2026-Q1 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 11
- Caligan Partners LP$35M
- VANGUARD CAPITAL MANAGEMENT LLC$22M
- GREAT POINT PARTNERS LLC$7M
- VANGUARD FIDUCIARY TRUST CO$4M
- MILLENNIUM MANAGEMENT LLC$3M
- VANGUARD PORTFOLIO MANAGEMENT LLC$3M
Full exits 3
- VANGUARD GROUP INC$25M
- Longbow Finance SA$2M
- JANE STREET GROUP, LLC$706K
Largest adds
- Spruce Street Capital LP$11M
- BlackRock, Inc.$11M
- Nantahala Capital Management, LLC$11M
- Nan Fung Group Holdings Ltd$9M
- Deep Track Capital, LP$8M
- STATE STREET CORP$7M
Largest trims
- JENNISON ASSOCIATES LLC$5M
- Logos Global Management LP$4M
- JPMORGAN CHASE & CO$3M
- AMERIPRISE FINANCIAL INC$2M
- BANK OF AMERICA CORP /DE/$564K
- BARCLAYS PLC$561K
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| Deep Track Capital, LP | 3,352,804 | $83M | 11.3% | 2026-Q1 |
| BlackRock, Inc. added | 2,470,845 | $61M | 8.3% | 2026-Q1 |
| RA CAPITAL MANAGEMENT, L.P. | 2,208,604 | $54M | 7.5% | 2026-Q1 |
| TCG Crossover Management, LLC added | 1,839,489 | $45M | 6.2% | 2026-Q1 |
| Commodore Capital LP | 1,500,000 | $37M | 5.1% | 2026-Q1 |
| Caligan Partners LP new | 1,438,070 | $35M | 4.7% | 2026-Q1 |
| Spruce Street Capital LP added | 1,376,159 | $34M | 4.6% | 2026-Q1 |
| JPMORGAN CHASE & CO trimmed | 1,427,568 | $33M | 4.5% | 2026-Q1 |
| Trails Edge Capital Partners, LP trimmed | 1,319,362 | $33M | 4.5% | 2026-Q1 |
| Nantahala Capital Management, LLC added | 1,052,894 | $26M | 3.6% | 2026-Q1 |
| BALYASNY ASSET MANAGEMENT L.P. added | 923,694 | $23M | 3.1% | 2026-Q1 |
| Logos Global Management LP trimmed | 915,000 | $23M | 3.1% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 894,653 | $22M | 3.0% | 2026-Q1 |
| Alyeska Investment Group, L.P. added | 863,947 | $21M | 2.9% | 2026-Q1 |
| Vivo Capital, LLC | 800,000 | $20M | 2.7% | 2026-Q1 |
| Nan Fung Group Holdings Ltd added | 630,657 | $16M | 2.1% | 2026-Q1 |
| JENNISON ASSOCIATES LLC trimmed | 538,216 | $13M | 1.8% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 518,228 | $13M | 1.7% | 2026-Q1 |
| STATE STREET CORP added | 504,373 | $12M | 1.7% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 416,906 | $10M | 1.4% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 363,799 | $9M | 1.2% | 2026-Q1 |
| GREAT POINT PARTNERS LLC new | 300,000 | $7M | 1.0% | 2026-Q1 |
| FMR LLC added | 222,508 | $5M | 0.8% | 2026-Q1 |
| BAKER BROS. ADVISORS LP | 200,000 | $5M | 0.7% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 186,095 | $5M | 0.6% | 2026-Q1 |
| HighVista Strategies LLC added | 173,595 | $4M | 0.6% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 157,426 | $4M | 0.5% | 2026-Q1 |
| NORTHERN TRUST CORP added | 154,398 | $4M | 0.5% | 2026-Q1 |
| Integral Health Asset Management, LLC added | 150,000 | $4M | 0.5% | 2026-Q1 |
| UBS Group AG added | 137,932 | $3M | 0.5% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC trimmed | 136,966 | $3M | 0.5% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 112,497 | $3M | 0.4% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 108,307 | $3M | 0.4% | 2026-Q1 |
| Eversept Partners, LP new | 100,198 | $2M | 0.3% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 72,067 | $2M | 0.2% | 2026-Q1 |
| Boxer Capital Management, LLC | 70,000 | $2M | 0.2% | 2026-Q1 |
| JANUS HENDERSON GROUP PLC new | 65,429 | $2M | 0.2% | 2026-Q1 |
| WELLINGTON MANAGEMENT GROUP LLP trimmed | 52,640 | $1M | 0.2% | 2026-Q1 |
| STEMPOINT CAPITAL LP new | 50,000 | $1M | 0.2% | 2026-Q1 |
| MORGAN STANLEY added | 47,280 | $1M | 0.2% | 2026-Q1 |
| Bank of New York Mellon Corp added | 45,457 | $1M | 0.2% | 2026-Q1 |
| ACUTA CAPITAL PARTNERS, LLC trimmed | 28,919 | $713K | 0.1% | 2026-Q1 |
| Calamos Advisors LLC new | 24,063 | $593K | 0.1% | 2026-Q1 |
| Nuveen, LLC | 22,966 | $566K | 0.1% | 2026-Q1 |
| Focus Partners Wealth trimmed | 19,815 | $489K | 0.1% | 2026-Q1 |
| RHUMBLINE ADVISERS added | 17,103 | $422K | 0.1% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ trimmed | 16,618 | $410K | 0.1% | 2026-Q1 |
| DEUTSCHE BANK AG\ added | 15,359 | $379K | 0.1% | 2026-Q1 |
| MEYER HANDELMAN CO new | 15,094 | $372K | 0.1% | 2026-Q1 |
| Opaleye Management Inc. new | 14,506 | $358K | 0.0% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 13,229 | $327K | 0.0% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP | 12,720 | $314K | 0.0% | 2026-Q1 |
| MetLife Investment Management, LLC | 11,104 | $274K | 0.0% | 2026-Q1 |
| Invesco Ltd. trimmed | 10,729 | $265K | 0.0% | 2026-Q1 |
| Soleus Capital Management, L.P. | 10,000 | $247K | 0.0% | 2026-Q1 |
| Quadrature Capital Ltd new | 9,931 | $245K | 0.0% | 2026-Q1 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. added | 9,170 | $226K | 0.0% | 2026-Q1 |
| Vanguard Global Advisers, LLC new | 8,753 | $216K | 0.0% | 2026-Q1 |
| WELLS FARGO & COMPANY/MN trimmed | 8,623 | $213K | 0.0% | 2026-Q1 |
| NEW YORK STATE COMMON RETIREMENT FUND new | 6,100 | $150K | 0.0% | 2026-Q1 |
| Police & Firemen's Retirement System of New Jersey added | 6,041 | $149K | 0.0% | 2026-Q1 |
| CITIGROUP INC added | 5,569 | $137K | 0.0% | 2026-Q1 |
| STRS OHIO added | 5,100 | $126K | 0.0% | 2026-Q1 |
| FEDERATED HERMES, INC. | 5,000 | $123K | 0.0% | 2026-Q1 |
| BARCLAYS PLC trimmed | 4,530 | $112K | 0.0% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS added | 4,052 | $100K | 0.0% | 2026-Q1 |
| Legal & General Group Plc trimmed | 1,723 | $42K | 0.0% | 2026-Q1 |
| Tower Research Capital LLC (TRC) added | 1,661 | $41K | 0.0% | 2026-Q1 |
| Ameritas Investment Partners, Inc. | 1,562 | $39K | 0.0% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 1,041 | $26K | 0.0% | 2026-Q1 |
| Sterling Capital Management LLC trimmed | 368 | $9K | 0.0% | 2026-Q1 |
| GAMMA Investing LLC added | 162 | $4K | 0.0% | 2026-Q1 |
| PNC FINANCIAL SERVICES GROUP, INC. new | 145 | $4K | 0.0% | 2026-Q1 |
| MassMutual Private Wealth & Trust, FSB new | 54 | $1K | 0.0% | 2026-Q1 |
| CWM, LLC added | 29 | $715 | 0.0% | 2026-Q1 |
| VANGUARD GROUP INC new | 1,112,978 | $25M | 3.4% | 2025-Q4 stale |
| ADAGE CAPITAL PARTNERS GP, L.L.C. new | 200,000 | $3M | 0.4% | 2025-Q3 stale |
| Longbow Finance SA new | 82,336 | $2M | 0.3% | 2025-Q4 stale |
| SILVERARC CAPITAL MANAGEMENT, LLC new | 70,000 | $1M | 0.2% | 2025-Q3 stale |
| HRT FINANCIAL LP new | 58,815 | $928K | 0.1% | 2025-Q3 stale |
| JANE STREET GROUP, LLC added | 31,733 | $706K | 0.1% | 2025-Q4 stale |
| Monashee Investment Management LLC new | 40,000 | $632K | 0.1% | 2025-Q3 stale |
| TD Asset Management Inc new | 36,780 | $581K | 0.1% | 2025-Q3 stale |
| Point72 (DIFC) Ltd new | 34,003 | $537K | 0.1% | 2025-Q3 stale |
| NORGES BANK new | 20,000 | $445K | 0.1% | 2025-Q4 stale |
| Hudson Bay Capital Management LP | 27,097 | $428K | 0.1% | 2025-Q4 stale |
| XTX Topco Ltd added | 19,121 | $426K | 0.1% | 2025-Q4 stale |
| MARSHALL WACE, LLP trimmed | 18,014 | $401K | 0.1% | 2025-Q4 stale |
| Squarepoint Ops LLC new | 20,825 | $329K | 0.0% | 2025-Q3 stale |
| Jefferies Financial Group Inc. trimmed | 12,445 | $277K | 0.0% | 2025-Q4 stale |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE new | 17,488 | $276K | 0.0% | 2025-Q3 stale |
| ARISTEIA CAPITAL, L.L.C. new | 15,270 | $241K | 0.0% | 2025-Q3 stale |
| Point72 Asia (Singapore) Pte. Ltd. new | 14,535 | $230K | 0.0% | 2025-Q3 stale |
| Quantessence Capital LLC new | 14,225 | $225K | 0.0% | 2025-Q3 stale |
| Brevan Howard Capital Management LP new | 13,259 | $209K | 0.0% | 2025-Q3 stale |
| LANDSCAPE CAPITAL MANAGEMENT, L.L.C. new | 10,638 | $168K | 0.0% | 2025-Q3 stale |
| SG Americas Securities, LLC new | 6,434 | $143K | 0.0% | 2025-Q4 stale |
| Persistent Asset Partners Ltd new | 4,080 | $91K | 0.0% | 2025-Q4 stale |
| ROYAL BANK OF CANADA new | 767 | $17K | 0.0% | 2025-Q4 stale |
| AMALGAMATED BANK new | 605 | $13K | 0.0% | 2025-Q4 stale |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.