Among active 13F managers last quarter, 11 opened and 11 added, while 6 reduced; the largest holder to move was Boxer Capital Management, LLC (+44%). Over the last 180 days, 4 insiders sold and 1 insider bought, a net -$4.2M in open-market trades.
The legs disagree, or only one of them leans.
58 tracked 13F filers disclose a position in SRZN as of the latest SEC 13F filings, a combined $271.0M in reported value. Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.
| # | Fund | Shares | Position value | Last move | As of | History |
|---|---|---|---|---|---|---|
| 1 | TCG Crossover Management, LLC | 1.5M | $38.2M | —Held | Q2 2026 | |
| 2 | Boxer Capital Management, LLC | 1.1M | $27.0M | ▲+44% Added · +339K sh | Q2 2026 | |
| 3 | Millennium Management LLC | 731K | $21.3M | ▲+1.4% Added · +10K sh | Q1 2026 | |
| 4 | Point72 Asset Management, L.P. | 664K | $17.2M | ▲New +664K sh | Q2 2026 | |
| 5 | Venrock Adviser, LLC | 633K | $16.4M | —Held | Q2 2026 | |
| 6 | Stempoint Capital LP | 603K | $13.8M | ▲+15% Added · +77K sh | Q2 2026 | |
| 7 | Perceptive Advisors LLC | 504K | $13.1M | ▲+120% Added · +275K sh | Q2 2026 | |
| 8 | Spruce Street Capital LP | 432K | $11.2M | —Held | Q2 2026 | |
| 9 | BlackRock, Inc. | 395K | $10.2M | ▲14× Added · +367K sh | Q2 2026 | |
| 10 | Vanguard Capital Management LLC | 393K | $10.2M | ▲+132% Added · +223K sh | Q2 2026 | |
| 11 | Braidwell LP | 391K | $10.1M | ▼−1.3% Reduced · −5K sh | Q2 2026 | |
| 12 | Kalehua Capital Management LLC | 385K | $10.0M | —Held | Q2 2026 | |
| 13 | Vestal Point Capital, LP | 305K | $7.9M | ▼−10% Reduced · −34K sh | Q2 2026 | |
| 14 | 5AM Venture Management, LLC | 271K | $7.0M | ▼−30% Reduced · −116K sh | Q2 2026 | |
| 15 | Vivo Capital, LLC | 260K | $6.7M | —Held | Q2 2026 | |
| 16 | Balyasny Asset Management L.P. | 204K | $5.9M | ▲+7.0% Added · +13K sh | Q1 2026 | |
| 17 | Geode Capital Management, LLC | 202K | $5.2M | ▲+206% Added · +136K sh | Q2 2026 | |
| 18 | Acuta Capital Partners, LLC | 173K | $4.5M | ▲+0.3% Added · +548 sh | Q2 2026 | |
| 19 | Ameriprise Financial Inc | 160K | $4.7M | ▲+143% Added · +94K sh | Q1 2026 | |
| 20 | Regents Of The University Of California | 133K | $3.9M | —Held | Q1 2026 | |
| 21 | State Street Corp | 133K | $3.5M | ▲+380% Added · +105K sh | Q2 2026 | |
| 22 | Adage Capital Partners GP, L.L.C. | 89K | $2.6M | —Held | Q1 2026 | |
| 23 | Euclidean Capital LLC | 88K | $2.3M | —Held | Q2 2026 | |
| 24 | Fred Alger Management, LLC | 72K | $2.1M | ▼−28% Reduced · −28K sh | Q1 2026 | |
| 25 | Vanguard Fiduciary Trust Co | 60K | $1.5M | ▲+68% Added · +24K sh | Q2 2026 |
Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.
Last quarter, 11 funds opened a new position in SRZN and 11 added to an existing one, while 6 reduced. Based on 13F filings from active, signal-eligible managers (passive index funds and other mechanical holders are excluded from this count).
| Company | Co-held by | Their position there |
|---|---|---|
| Tango Therapeutics IncTNGX | 25 funds | $1.5B |
| Erasca IncERAS | 25 funds | $751.3M |
| Eli Lilly & CoLLY | 23 funds | $19.7B |
| Unitedhealth Group IncUNH | 23 funds | $12.4B |
| Intuitive Surgical IncISRG | 23 funds | $7.0B |
| Revolution Medicines IncRVMD | 23 funds | $1.8B |
| Cogent Biosciences IncCOGT | 23 funds | $753.1M |
| Nvidia CorpNVDA | 22 funds | $91.1B |
| JPMorgan Chase & CoJPM | 22 funds | $12.7B |
| Boston Scientific CorpBSX | 22 funds | $2.6B |
| Biogen IncBIIB | 22 funds | $928.0M |
| Dianthus Therapeutics IncDNTH | 22 funds | $920.2M |
Ranked by how many of SRZN's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in SRZN.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Jul 22, 2026 | TCG Crossover GP II, LLC | 10% Owner | Sell (S) 2 lots, same day | 325K | $6.9M |
| May 4, 2026 | Williams Charles O | Chief Operating Officer | Sell (S) | 2K | $68K |
| May 4, 2026 | Li Yang | Exec. Vice President, Research | Sell (S) | 2K | $53K |
| May 4, 2026 | Parker Craig C | Chief Executive Officer, Director | Sell (S) | 5K | $151K |
| Mar 24, 2026 | TCG Crossover Fund II, L.P. | 10% Owner | Buy (P) 2 lots, same day | 107K | $2.6M |
| Mar 23, 2026 | TCG Crossover Fund II, L.P. | 10% Owner | Buy (P) 2 lots, same day | 15K | $379K |
| Mar 16, 2026 | TCG Crossover Fund II, L.P. | 10% Owner | Buy (P) 2 lots, same day | 1K | $30K |
| Mar 13, 2026 | TCG Crossover Fund II, L.P. | 10% Owner | Buy (P) 2 lots, same day | 35K | $882K |
| Mar 12, 2026 | TCG Crossover Fund II, L.P. | 10% Owner | Buy (P) 2 lots, same day | 12K | $309K |
| Feb 12, 2026 | TCG Crossover Fund II, L.P. | 10% Owner | Buy (P) 2 lots, same day | 1K | $26K |
| Feb 11, 2026 | TCG Crossover Fund II, L.P. | 10% Owner | Buy (P) 2 lots, same day | 18K | $419K |
| Feb 3, 2026 | TCG Crossover GP III, LLC | 10% Owner | Buy (P) 2 lots, same day | 4K | $96K |
One row per insider, day and transaction code; shares and value are summed across the lots. Every lot is on the full insider page and in the filing.
Where institutional funds (13F), corporate insiders (Form 4) and US House members (STOCK Act) are buying or selling the same name in the same window. Green is buying, red is selling.
Insiders and Congress: last 180 days. Funds: latest 13F, top 100 holders incl. passive
| Source | Buying | Selling | Net |
|---|---|---|---|
13F funds Top 100 holders by value, passive included; the hero counts active managers only | 21 | 9 | – |
Insiders Form 4 open-market | 1 | 4 | -$4.2M |
US House STOCK Act trades | 0 | 0 | $0 |
Capital Rotation reports where institutional capital disclosed rotating, as of the latest public SEC 13F filings. It is data, not investment advice, a recommendation, or a prediction. Filings lag about 45 days and cover long US equity positions only. Past disclosed flows do not indicate future prices. Do your own research; consult a licensed advisor.
| Class | 13F holders | Value held |
|---|---|---|
| SRZNthis pageEquity | 58 funds | $271.0M |
| 86889P117WARRANTS | 14 funds | $161K |
| 86889P109COM | 1 funds | $49.7M |
Same issuer, multiple share classes. The consensus leaderboards count this company once across all classes; this is the per-class detail.
Connected entities for SRZN
This stock page is the public Follow view. For one current, evidence-backed answer, use capital_change_brief through REST or MCP. It compares tracked 13F changes with qualifying Form 4 activity and cites the SEC evidence.
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/stocks/SRZN/capital-change-brief"
Use Arkolith's capital_change_brief for SRZN. Tell me what changed, whether insider activity corroborates it, and cite the SEC evidence.
13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for SRZN. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.