Among active 13F managers last quarter, 4 opened and 32 added, while 20 reduced; the largest holder to move was RTW Investments, LP (+0.7%). Over the last 180 days, 4 insiders sold and none bought, a net -$7.9M in open-market trades.
The legs disagree, or only one of them leans.
169 tracked 13F filers disclose a position in CSTL as of the latest SEC 13F filings, a combined $630.4M 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 | BlackRock, Inc. | 3.3M | $78.5M | ▲+10% Added · +309K sh | Q2 2026 | |
| 2 | RTW Investments, LP | 2.8M | $66.3M | ▲+0.7% Added · +20K sh | Q2 2026 | |
| 3 | Principal Financial Group Inc | 1.8M | $43.5M | ▼−2.1% Reduced · −38K sh | Q1 2026 | |
| 4 | Vanguard Capital Management LLC | 1.2M | $29.3M | ▲+4.2% Added · +49K sh | Q2 2026 | |
| 5 | Dimensional Fund Advisors LP | 1.0M | $25.5M | ▼−9.1% Reduced · −104K sh | Q1 2026 | |
| 6 | Vanguard Portfolio Management LLC | 841K | $20.1M | ▼−2.4% Reduced · −21K sh | Q2 2026 | |
| 7 | Summit Partners Public Asset Management, LLC | 825K | $19.7M | ▼−12% Reduced · −116K sh | Q2 2026 | |
| 8 | State Street Corp | 822K | $19.6M | ▲+6.9% Added · +53K sh | Q2 2026 | |
| 9 | Allianz Asset Management GmbH | 811K | $19.9M | ▲+30% Added · +189K sh | Q1 2026 | |
| 10 | Geode Capital Management, LLC | 796K | $19.0M | ▲+9.3% Added · +68K sh | Q2 2026 | |
| 11 | Jefferies Financial Group Inc. | 647K | $15.4M | ▲New +647K sh | Q2 2026 | |
| 12 | Qube Research & Technologies Ltd | 560K | $13.7M | ▲+138% Added · +324K sh | Q1 2026 | |
| 13 | AIGH Capital Management LLC | 545K | $13.0M | ▼−7.7% Reduced · −46K sh | Q2 2026 | |
| 14 | Renaissance Technologies LLC | 533K | $13.1M | ▲+8.1% Added · +40K sh | Q1 2026 | |
| 15 | Nuveen, LLC | 522K | $12.8M | ▼−0.5% Reduced · −3K sh | Q1 2026 | |
| 16 | Morgan Stanley | 429K | $10.5M | ▲+111% Added · +225K sh | Q1 2026 | |
| 17 | Point72 Asset Management, L.P. | 357K | $8.5M | ▲New +357K sh | Q2 2026 | |
| 18 | Millennium Management LLC | 353K | $8.7M | ▲+14% Added · +44K sh | Q1 2026 | |
| 19 | Goldman Sachs Group Inc | 341K | $8.4M | ▲+19% Added · +54K sh | Q1 2026 | |
| 20 | Connor, Clark & Lunn Investment Management Ltd. | 332K | $7.9M | ▼−12% Reduced · −45K sh | Q2 2026 | |
| 21 | Portolan Capital Management, LLC | 329K | $7.8M | ▼−76% Reduced · −1.0M sh | Q2 2026 | |
| 22 | Panagora Asset Management Inc | 301K | $7.2M | ▲+35% Added · +79K sh | Q2 2026 | |
| 23 | Schroder Investment Management Group | 299K | $7.0M | ▼−39% Reduced · −193K sh | Q1 2026 | |
| 24 | Allspring Global Investments Holdings, LLC | 292K | $7.0M | ▲+82% Added · +132K sh | Q2 2026 | |
| 25 | Wasatch Advisors LP | 279K | $6.7M | ▼−39% Reduced · −176K 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, 4 funds opened a new position in CSTL and 32 added to an existing one, while 20 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 |
|---|---|---|
| Nvidia CorpNVDA | 93 funds | $279.2B |
| Microsoft CorpMSFT | 93 funds | $177.6B |
| Eli Lilly & CoLLY | 92 funds | $57.4B |
| Apple IncAAPL | 91 funds | $198.2B |
| Amazon.com IncAMZN | 91 funds | $134.7B |
| Broadcom IncAVGO | 91 funds | $118.6B |
| Visa Inc-Class A SharesV | 91 funds | $41.5B |
| Costco Wholesale CorpCOST | 91 funds | $24.7B |
| Alphabet Inc-CL AGOOGL | 90 funds | $122.9B |
| JPMorgan Chase & CoJPM | 89 funds | $42.4B |
| Advanced Micro DevicesAMD | 89 funds | $40.0B |
| Lam Research CorpLRCX | 89 funds | $33.9B |
Ranked by how many of CSTL's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in CSTL.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Sep 1, 2026 | Oelschlager Kristen M | Chief Operating Officer | Sell (S) 2 lots, same day | 4K | $139K |
| Aug 31, 2026 | Juvenal Tobin W | Chief Commercial Officer | Sell (S) | 2K | $57K |
| Aug 28, 2026 | Maetzold Derek J | Pres. & Chief Exec. Officer, Director | Sell (S) 14 lots, same day | 19K | $616K |
| Aug 25, 2026 | Juvenal Tobin W | Chief Commercial Officer | Sell (S) | 9K | $317K |
| Aug 25, 2026 | Oelschlager Kristen M | Chief Operating Officer | Sell (S) 2 lots, same day | 12K | $426K |
| Aug 24, 2026 | Oelschlager Kristen M | Chief Operating Officer | Sell (S) | 12K | $412K |
| Aug 17, 2026 | Juvenal Tobin W | Chief Commercial Officer | Sell (S) | 2K | $51K |
| Aug 14, 2026 | Maetzold Derek J | Pres. & Chief Exec. Officer, Director | Sell (S) 7 lots, same day | 7K | $217K |
| Aug 14, 2026 | Stokes Frank | Chief Financial Officer | Sell (S) | 25K | $742K |
| Aug 5, 2026 | Maetzold Derek J | Pres. & Chief Exec. Officer, Director | Sell (S) 3 lots, same day | 4K | $110K |
| Aug 4, 2026 | Maetzold Derek J | Pres. & Chief Exec. Officer, Director | Sell (S) 6 lots, same day | 35K | $1.1M |
| Aug 3, 2026 | Oelschlager Kristen M | Chief Operating Officer | Sell (S) 3 lots, same day | 9K | $256K |
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 | 52 | 35 | – |
Insiders Form 4 open-market | 0 | 4 | -$7.9M |
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 CSTL
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/CSTL/capital-change-brief"
Use Arkolith's capital_change_brief for CSTL. 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 CSTL. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.