Among active 13F managers last quarter, 19 opened and none reduced or exited; the largest holder to move was ARCH Venture Management, LLC (new position). Over the last 180 days, 2 insiders bought and none sold, a net +$20.0M in open-market trades.
Funds lean in and no leg opposes.
29 tracked 13F filers disclose a position in SPTX as of the latest SEC 13F filings, a combined $589.5M 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 | ARCH Venture Management, LLC | 6.3M | $136.6M | ▲New +6.3M sh | Q2 2026 | |
| 2 | General Atlantic, L.P. | 6.1M | $132.5M | ▲New +6.1M sh | Q2 2026 | |
| 3 | Sofinnova Investments, Inc. | 3.6M | $77.4M | ▲New +3.6M sh | Q2 2026 | |
| 4 | TRV GP VI, LLC | 2.1M | $44.8M | ▲New +2.1M sh | Q2 2026 | |
| 5 | Foresite Capital Management VI LLC | 1.8M | $38.7M | ▲New +1.8M sh | Q2 2026 | |
| 6 | Price T Rowe Associates Inc | 1.3M | Withheld | ▲New +1.3M sh | Q2 2026 | |
| 7 | FMR LLC | 1.2M | $25.7M | ▲New +1.2M sh | Q2 2026 | |
| 8 | Bellevue Group AG | 1.1M | $23.9M | ▲New +1.1M sh | Q2 2026 | |
| 9 | Siren, L.L.C. | 1.1M | $23.8M | ▲New +1.1M sh | Q2 2026 | |
| 10 | Ra Capital Management, L.P. | 700K | $15.2M | ▲New +700K sh | Q2 2026 | |
| 11 | Vanguard Capital Management LLC | 599K | $13.0M | ▲New +599K sh | Q2 2026 | |
| 12 | Woodline Partners LP | 586K | $12.7M | ▲New +586K sh | Q2 2026 | |
| 13 | Perceptive Advisors LLC | 500K | $10.9M | ▲New +500K sh | Q2 2026 | |
| 14 | Braidwell LP | 500K | $10.9M | ▲New +500K sh | Q2 2026 | |
| 15 | BlackRock, Inc. | 230K | $5.0M | ▲New +230K sh | Q2 2026 | |
| 16 | Citadel Advisors LLC | 191K | $4.2M | ▲New +191K sh | Q2 2026 | |
| 17 | Geode Capital Management, LLC | 176K | $3.8M | ▲New +176K sh | Q2 2026 | |
| 18 | Pier Capital, LLC | 170K | $3.7M | ▲New +170K sh | Q2 2026 | |
| 19 | Vanguard Fiduciary Trust Co | 88K | $1.9M | ▲New +88K sh | Q2 2026 | |
| 20 | Alyeska Investment Group, L.P. | 75K | $1.6M | ▲New +75K sh | Q2 2026 | |
| 21 | ALPS Advisors Inc | 54K | $1.2M | ▲New +54K sh | Q2 2026 | |
| 22 | DAFNA Capital Management LLC | 32K | $704K | ▲New +32K sh | Q2 2026 | |
| 23 | Ghisallo Capital Management LLC | 25K | $543K | ▲New +25K sh | Q2 2026 | |
| 24 | Weiss Asset Management LP | 10K | $217K | ▲New +10K sh | Q2 2026 | |
| 25 | Zimmer Partners, LP | 10K | $217K | ▲New +10K 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. 1 value row is withheld because the reported units disagree with same-security peers; share counts are unchanged.
Last quarter, 19 funds opened a new position in SPTX, 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 |
|---|---|---|
| Tango Therapeutics IncTNGX | 5 funds | $226.9M |
| Definium Therapeutics IncDFTX | 5 funds | $85.3M |
| Revolution Medicines IncRVMD | 4 funds | $441.2M |
| Rapport Therapeutics IncRAPP | 4 funds | $301.9M |
| Veradermics IncMANE | 4 funds | $223.5M |
| Vera Therapeutics IncVERA | 4 funds | $222.9M |
| Rhythm Pharmaceuticals IncRYTM | 4 funds | $213.9M |
| Oruka Therapeutics IncORKA | 4 funds | $212.7M |
| Spyre Therapeutics IncSYRE | 4 funds | $187.1M |
| Arrowhead Pharmaceuticals InARWR | 4 funds | $155.7M |
Ranked by how many of SPTX's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in SPTX.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Jun 22, 2026 | Hombach Robert J. | Director | Buy (P) | 13K | $236K |
| May 4, 2026 | ARCH Venture Partners XII, LLC | 10% Owner | Buy (P) | 1.1M | $19.8M |
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 | +$20.0M |
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 SPTX
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/SPTX/capital-change-brief"
Use Arkolith's capital_change_brief for SPTX. 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 SPTX. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.