The public view is the crawlable proof. The same sourced dataset is available through REST and MCP for agents, research scripts, and back-office tools.
This stock page is the Follow view. The Build view lets your agent query QUMSU owners, fund changes, insider filings, and source links through REST or MCP.
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/stocks/QUMSU"
Use Arkolith to show who owns QUMSU, which funds added or reduced it, and which SEC filings prove each claim.
| # | Fund | Position value | Shares | Last move | As of | History |
|---|---|---|---|---|---|---|
| 1 | Westchester Capital Management, LLC | $1.0M | 100K | —Held | Q1 2026 | |
| 2 | Clear Street Group Inc. | $232K | 22K | ▲+51% Added · +8K sh | Q1 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.
No Form 4 insider transactions on file yet.
| Class | 13F holders | Value held |
|---|---|---|
| QUMSORD SHS | 20 funds | $53.7M |
| QUMSRSPACS | 19 funds | $1.4M |
| QUMSUthis pageUNIT 07/30/2030 | 5 funds | $1.9M |
Same issuer, multiple share classes. The consensus leaderboards count this company once across all classes; this is the per-class detail.
| Company | Co-held by | Combined value |
|---|---|---|
| HAYMAKER ACQUISITION CORP 4HYAC | 9 funds | $43.7M |
| CARTESIAN GROWTH CORP I-CL ACGCT | 9 funds | $37.8M |
| SOLARIUS CAPITAL ACQUIS-CL ASOCA | 9 funds | $37.7M |
| CANTOR EQUITY PARTNERS III-ACAEP | 9 funds | $31.1M |
| FUTURECREST ACQUISITION CORPFCRS/U | 9 funds | $12.7M |
| MICROSOFT CORPMSFT | 8 funds | $93.4B |
| APPLE INCAAPL | 8 funds | $68.1B |
| TESLA INCTSLA | 8 funds | $24.7B |
| AMERICAN EXPRESS COAXP | 8 funds | $8.1B |
| BERKSHIRE HATHAWAY INC-CL BBRK/B | 8 funds | $8.1B |
| BOOKING HOLDINGS INCBKNG | 8 funds | $7.5B |
| GOLDMAN SACHS GROUP INCGS | 8 funds | $6.3B |
Ranked by how many of QUMSU's institutional holders also hold each name, a cross-fund conviction signal. Via the MCP server (ticker.co_held).
No filings captured for this ticker in the live stream yet.
13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for QUMSU. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes. Every panel above is one call to the Arkolith API & MCP server.