Who owns SRZN (SRZN)
Which tracked institutional funds hold SRZN, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See SRZN 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 SRZN is one-sided between 2025-Q4 and 2026-Q1: 33 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
SRZN’s largest tracked holder by dollar value, Column Group LLC, sizes it at 55.4% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 55.4pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in SRZN 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 68 tracked filers holding SRZN, 35 increased or opened the position and 25 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 SRZN 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 5
- TCG Crossover Management, LLC$43M
- Vestal Point Capital, LP$10M
- VANGUARD CAPITAL MANAGEMENT LLC$5M
- TWO SIGMA INVESTMENTS, LP$1M
- VANGUARD FIDUCIARY TRUST CO$1M
Full exits 6
- VANGUARD GROUP INC$7M
- Nantahala Capital Management, LLC$5M
- Empery Asset Management, LP$2M
- Schonfeld Strategic Advisors LLC$2M
- Walleye Capital LLC$928K
- BANK OF AMERICA CORP /DE/$669K
Largest adds
- Column Group LLC$14M
- Boxer Capital Management, LLC$13M
- Kalehua Capital Management LLC$9M
- PERCEPTIVE ADVISORS LLC$7M
- MILLENNIUM MANAGEMENT LLC$5M
- Venrock Adviser, LLC$4M
Largest trims
- STEMPOINT CAPITAL LP$7M
- Stonepine Capital Management, LLC$2M
- Eversept Partners, LP$446K
- JANE STREET GROUP, LLC$418K
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 |
|---|---|---|---|---|
| Column Group LLC added | 1,916,950 | $56M | 18.6% | 2026-Q1 |
| TCG Crossover Management, LLC new | 1,473,101 | $43M | 14.3% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC added | 731,138 | $21M | 7.1% | 2026-Q1 |
| Venrock Adviser, LLC | 632,931 | $18M | 6.1% | 2026-Q1 |
| Spruce Street Capital LP | 432,040 | $13M | 4.2% | 2026-Q1 |
| BRAIDWELL LP trimmed | 396,100 | $12M | 3.8% | 2026-Q1 |
| 5AM Venture Management, LLC | 387,500 | $11M | 3.8% | 2026-Q1 |
| Kalehua Capital Management LLC | 385,178 | $11M | 3.7% | 2026-Q1 |
| Vestal Point Capital, LP new | 338,611 | $10M | 3.3% | 2026-Q1 |
| Vivo Capital, LLC | 260,000 | $8M | 2.5% | 2026-Q1 |
| Woodline Partners LP trimmed | 227,848 | $7M | 2.2% | 2026-Q1 |
| BALYASNY ASSET MANAGEMENT L.P. added | 203,888 | $6M | 2.0% | 2026-Q1 |
| STEMPOINT CAPITAL LP trimmed | 195,981 | $6M | 1.9% | 2026-Q1 |
| Ikarian Capital, LLC added | 173,107 | $5M | 1.7% | 2026-Q1 |
| ACUTA CAPITAL PARTNERS, LLC trimmed | 172,847 | $5M | 1.7% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 169,092 | $5M | 1.6% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC added | 159,711 | $5M | 1.6% | 2026-Q1 |
| SILVERARC CAPITAL MANAGEMENT, LLC trimmed | 144,255 | $4M | 1.4% | 2026-Q1 |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | 88,653 | $3M | 0.9% | 2026-Q1 |
| FRED ALGER MANAGEMENT, LLC trimmed | 71,697 | $2M | 0.7% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC trimmed | 65,849 | $2M | 0.6% | 2026-Q1 |
| Eversept Partners, LP trimmed | 58,624 | $2M | 0.6% | 2026-Q1 |
| ArrowMark Colorado Holdings LLC trimmed | 55,123 | $2M | 0.5% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC added | 49,126 | $1M | 0.5% | 2026-Q1 |
| BOOTHBAY FUND MANAGEMENT, LLC added | 47,299 | $1M | 0.5% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP new | 39,482 | $1M | 0.4% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 35,469 | $1M | 0.3% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 35,390 | $1M | 0.3% | 2026-Q1 |
| Stonepine Capital Management, LLC trimmed | 33,005 | $961K | 0.3% | 2026-Q1 |
| 683 Capital Management, LLC trimmed | 33,000 | $961K | 0.3% | 2026-Q1 |
| BlackRock, Inc. added | 27,851 | $811K | 0.3% | 2026-Q1 |
| STATE STREET CORP added | 27,726 | $808K | 0.3% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 25,851 | $753K | 0.3% | 2026-Q1 |
| LMR Partners LLP trimmed | 23,557 | $686K | 0.2% | 2026-Q1 |
| MORGAN STANLEY trimmed | 22,446 | $654K | 0.2% | 2026-Q1 |
| UBS Group AG added | 21,247 | $619K | 0.2% | 2026-Q1 |
| MARSHALL WACE, LLP added | 18,930 | $551K | 0.2% | 2026-Q1 |
| Qube Research & Technologies Ltd new | 14,516 | $423K | 0.1% | 2026-Q1 |
| NORTHERN TRUST CORP trimmed | 12,265 | $357K | 0.1% | 2026-Q1 |
| HRT FINANCIAL LP added | 12,155 | $354K | 0.1% | 2026-Q1 |
| ADAR1 Capital Management, LLC added | 12,000 | $350K | 0.1% | 2026-Q1 |
| Alyeska Investment Group, L.P. | 10,188 | $297K | 0.1% | 2026-Q1 |
| Hudson Bay Capital Management LP trimmed | 8,653 | $252K | 0.1% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS added | 7,325 | $213K | 0.1% | 2026-Q1 |
| Persistent Asset Partners Ltd added | 7,143 | $208K | 0.1% | 2026-Q1 |
| JANE STREET GROUP, LLC trimmed | 7,091 | $207K | 0.1% | 2026-Q1 |
| EcoR1 Capital, LLC | 4,444 | $129K | 0.0% | 2026-Q1 |
| Vanguard Global Advisers, LLC new | 2,570 | $75K | 0.0% | 2026-Q1 |
| China Universal Asset Management Co., Ltd. added | 2,500 | $73K | 0.0% | 2026-Q1 |
| BARCLAYS PLC added | 1,888 | $55K | 0.0% | 2026-Q1 |
| ACADIAN ASSET MANAGEMENT LLC | 1,508 | $43K | 0.0% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 1,119 | $31K | 0.0% | 2026-Q1 |
| ROYAL BANK OF CANADA added | 625 | $18K | 0.0% | 2026-Q1 |
| BAKER BROS. ADVISORS LP | 833,333 | $13K | 0.0% | 2026-Q1 |
| BRIDGER MANAGEMENT, LLC | 442,052 | $7K | 0.0% | 2026-Q1 |
| Euclidean Capital LLC added | 170,833 | $3K | 0.0% | 2026-Q1 |
| PERCEPTIVE ADVISORS LLC | 166,666 | $3K | 0.0% | 2026-Q1 |
| DEERFIELD MANAGEMENT COMPANY, L.P. | 166,666 | $3K | 0.0% | 2026-Q1 |
| SymBiosis Capital Partners, LLC | 150,000 | $2K | 0.0% | 2026-Q1 |
| REGENTS OF THE UNIVERSITY OF CALIFORNIA trimmed | 83,333 | $1K | 0.0% | 2026-Q1 |
| Boxer Capital Management, LLC trimmed | 66,666 | $1K | 0.0% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 41,666 | $1K | 0.0% | 2026-Q1 |
| FEDERATED HERMES, INC. new | 29 | $845 | 0.0% | 2026-Q1 |
| Trustees of Columbia University in the City of New York | 33,333 | $533 | 0.0% | 2026-Q1 |
| WOLVERINE ASSET MANAGEMENT LLC added | 3,085 | $49 | 0.0% | 2026-Q1 |
| Tower Research Capital LLC (TRC) trimmed | 1 | $29 | 0.0% | 2026-Q1 |
| Clear Street Group Inc. | 100 | $2 | 0.0% | 2026-Q1 |
| Virtu Financial LLC added | 11,071 | — | 0.0% | 2026-Q1 |
| RA CAPITAL MANAGEMENT, L.P. | 602,626 | $8M | 2.6% | 2025-Q3 stale |
| VANGUARD GROUP INC added | 319,236 | $7M | 2.4% | 2025-Q4 stale |
| Nantahala Capital Management, LLC | 229,527 | $5M | 1.7% | 2025-Q4 stale |
| Empery Asset Management, LP trimmed | 103,974 | $2M | 0.8% | 2025-Q4 stale |
| Schonfeld Strategic Advisors LLC added | 74,645 | $2M | 0.6% | 2025-Q4 stale |
| Walleye Capital LLC added | 41,041 | $928K | 0.3% | 2025-Q4 stale |
| Board of Trustees of The Leland Stanford Junior University | 52,130 | $672K | 0.2% | 2025-Q3 stale |
| BANK OF AMERICA CORP /DE/ added | 29,608 | $669K | 0.2% | 2025-Q4 stale |
| Driehaus Capital Management LLC trimmed | 67,566 | $604K | 0.2% | 2025-Q2 stale |
| ARMISTICE CAPITAL, LLC trimmed | 60,000 | $536K | 0.2% | 2025-Q2 stale |
| HEIGHTS CAPITAL MANAGEMENT, INC added | 44,978 | $524K | 0.2% | 2025-Q1 stale |
| Brevan Howard Capital Management LP new | 18,921 | $428K | 0.1% | 2025-Q4 stale |
| Quadrature Capital Ltd new | 14,802 | $335K | 0.1% | 2025-Q4 stale |
| OMERS ADMINISTRATION Corp new | 13,700 | $310K | 0.1% | 2025-Q4 stale |
| IEQ CAPITAL, LLC new | 13,471 | $304K | 0.1% | 2025-Q4 stale |
| CITIGROUP INC new | 1,062 | $24K | 0.0% | 2025-Q4 stale |
| SAMSARA BIOCAPITAL, LLC trimmed | 99,999 | $2K | 0.0% | 2025-Q3 stale |
| CANTOR FITZGERALD, L. P. | 70,824 | $1K | 0.0% | 2025-Q2 stale |
| PRELUDE CAPITAL MANAGEMENT, LLC | 24,614 | $738 | 0.0% | 2025-Q1 stale |
| Monashee Investment Management LLC trimmed | 30,129 | $545 | 0.0% | 2025-Q2 stale |
| SBI Securities Co., Ltd. new | 2 | $26 | 0.0% | 2025-Q3 stale |
| CLEAR STREET LLC | 100 | $2 | 0.0% | 2025-Q2 stale |
| TORONTO DOMINION BANK new | 100 | $2 | 0.0% | 2025-Q2 stale |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | 0 | — | 0.0% | 2025-Q2 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.