Among active 13F managers last quarter, 13 opened and none reduced or exited; the largest holder to move was Ra Capital Management, L.P. (new position). Over the last 180 days, 2 insiders bought and none sold, a net $0 in open-market trades.
Funds lean in and no leg opposes.
15 tracked 13F filers disclose a position in JATT as of the latest SEC 13F filings, a combined $32.0M 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 | Ra Capital Management, L.P. | 500K | $5.7M | ▲New +500K sh | Q2 2026 | |
| 2 | Great Point Partners LLC | 500K | $5.7M | ▲New +500K sh | Q2 2026 | |
| 3 | Atika Capital Management LLC | 400K | $4.5M | ▲New +400K sh | Q2 2026 | |
| 4 | Citadel Advisors LLC | 320K | $3.6M | ▲New +320K sh | Q2 2026 | |
| 5 | Braidwell LP | 250K | $2.8M | ▲New +250K sh | Q2 2026 | |
| 6 | Nantahala Capital Management, LLC | 225K | $2.6M | ▲New +225K sh | Q2 2026 | |
| 7 | TCG Crossover Management, LLC | 200K | $2.3M | ▲New +200K sh | Q2 2026 | |
| 8 | Spruce Street Capital LP | 160K | $1.8M | ▲New +160K sh | Q2 2026 | |
| 9 | Logos Global Management LP | 100K | $1.1M | ▲New +100K sh | Q2 2026 | |
| 10 | Woodline Partners LP | 50K | $568K | ▲New +50K sh | Q2 2026 | |
| 11 | Magnetar Financial LLC | 48K | $544K | ▲New +48K sh | Q2 2026 | |
| 12 | 683 Capital Management, LLC | 42K | $480K | ▲New +42K sh | Q2 2026 | |
| 13 | Diadema Partners LP | 9K | $102K | ▲New +9K sh | Q2 2026 | |
| 14 | Clear Street Group Inc. | 7K | $81K | ▲New +7K sh | Q2 2026 | |
| 15 | Persistent Asset Partners Ltd | 2K | $26K | ▲New +2K 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, 13 funds opened a new position in JATT, while none reduced or exited. 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 |
|---|---|---|
| Abivax Sa-ADRABVX | 9 funds | $1.4B |
| Dianthus Therapeutics IncDNTH | 8 funds | $494.4M |
| LB Pharmaceuticals IncLBRX | 8 funds | $233.9M |
| Vor Biopharma IncVOR | 8 funds | $228.0M |
| Amylyx Pharmaceuticals IncAMLX | 8 funds | $181.3M |
| Avalo Therapeutics IncAVTX | 8 funds | $166.7M |
| Cogent Biosciences IncCOGT | 7 funds | $372.6M |
| Oruka Therapeutics IncORKA | 7 funds | $335.7M |
| Zai Lab Ltd-ADRZLAB | 7 funds | $301.4M |
| Definium Therapeutics IncDFTX | 7 funds | $227.3M |
| Inflarx NVIFRX | 7 funds | $67.7M |
| Amazon.com IncAMZN | 6 funds | $3.2B |
Ranked by how many of JATT's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in JATT.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Apr 20, 2026 | JATT Ventures II L.P. | 10% Owner | Buy (P) | 300K | — |
| Apr 20, 2026 | Sidhu Someit | Chief Executive Officer, Director, 10% Owner | Buy (P) | 300K | — |
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 | 0 | 0 | – |
Insiders Form 4 open-market | 2 | 0 | $0 |
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.
Connected entities for JATT
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/JATT/capital-change-brief"
Use Arkolith's capital_change_brief for JATT. 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 JATT. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.