# Marshfield Associates 13F holdings

> Latest reported SEC 13F equity book. Teaser: top 10 of 17 long-equity positions.
> CIK 914976. Latest filing Q1 2026, as of quarter end 2026-03-31. Long-equity book $5.0B.

## Top holdings (teaser)

| # | Ticker | Issuer | Value | % of book | Change |
|---|--------|--------|-------|-----------|--------|
| 1 | AZO | Autozone Inc | $557.4M | 11.2% | Reduced |
| 2 | UNH | Unitedhealth Group Inc | $511.6M | 10.2% | Added |
| 3 | PGR | Progressive Corp | $486.8M | 9.7% | Reduced |
| 4 | ROST | Ross Stores Inc | $394.0M | 7.9% | Reduced |
| 5 | V | Visa Inc | $379.3M | 7.6% | Added |
| 6 | ORLY | Oreilly Automotive Inc | $324.3M | 6.5% | Reduced |
| 7 | MA | Mastercard Incorporated | $299.9M | 6.0% | Reduced |
| 8 | ACGL | Arch Cap Group Ltd | $292.9M | 5.9% | Added |
| 9 | EXPD | Expeditors Intl Wash Inc | $279.7M | 5.6% | Reduced |
| 10 | DPZ | Dominos Pizza Inc | $270.9M | 5.4% | Reduced |

## Latest moves

Bought: UNH, V, ACGL
Sold: AZO, PGR, ROST

Counts and totals reflect the 13F filers and securities Arkolith tracks, not the entire institutional universe. Option legs are excluded from the book above.

## Full data via the API and MCP

This page is a teaser. The complete book, full quarter-over-quarter history, and per-datapoint
provenance are available through the metered REST API and MCP server.

- Endpoint: https://arkolith.com/api/mcp (transport: streamable-http)
- Auth: Bearer API key. Mint one and copy a ready-to-paste command at https://arkolith.com/connect
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- Discovery: `tools/list` is free; `tools/call` is metered by credits.

### Machine-readable
- Tool catalog JSON: https://arkolith.com/api/mcp/catalog
- MCP descriptor: https://arkolith.com/.well-known/mcp.json
- OpenAPI 3.1 REST spec: https://arkolith.com/openapi.json
- Full LLM guide: https://arkolith.com/llms-full.txt
- Human docs: https://arkolith.com/docs

## Source and method

- Source: SEC EDGAR 13F-HR (public domain). Long-equity positions only (option legs excluded). Filed quarterly, about a 45-day lag.
- Primary source: https://www.sec.gov/Archives/edgar/data/914976/000117266126002329/xslForm13F_X02/primary_doc.xml
- Human page: https://arkolith.com/fund/marshfield-associates-914976
- Per-datapoint lineage: call the `provenance.get` MCP tool for the source URL and fetch history behind any figure.

Paid product with a one-time evaluation grant at signup (no card to evaluate). Most calls cost 1 credit (~$0.01); heavier point-in-time / cross-source tools cost more.

_Latest disclosed public filings. Data, not investment advice._