13fmcp.ai

Release notes

What changed, and when

Each release lists what shipped. Figures about the data are computed in SQL over the loaded population, not estimated.

v1.0.0

27 October 2026filed

First release. 13fmcp.ai serves SEC Form 13F institutional holdings exactly as filed, over the Model Context Protocol, and links filings to registered advisers by CRD where the filed record or the SEC roster allows.

Data

  • Four SEC Form 13F data-set releases loaded: periods September–November 2025, December 2025–February 2026, March–May 2026 and June–August 2026.
  • 14,393,459 filed position rows across 45,407 submissions from 11,426 distinct filers, including amendments; every filing is kept.
  • Per-CIK-per-period current view: a RESTATEMENT amendment replaces the original, NEW HOLDINGS amendments add rows.
  • Filed VALUE stored in dollars; filings before 3 January 2023 are converted from the filed thousands and the applied rule is recorded.
  • Columns are mapped by header name with aliases; unmapped or missing columns are logged, never guessed by position.

MCP server

  • Twelve read-only tools: search_managers, get_manager, get_holdings, holding_changes, top_managers, security_holders, portfolio_overlap, cohort_stats, cohort_chart, list_skills, get_skill, server_info.
  • Seven skills served fresh from the database: form-13f-literacy, presentation-contract, manager-holdings-brief, market-sensitivity-read, holdings-change-monitor, buyer-seller-overlap, verify-a-holdings-claim.
  • Explicit typed output schema on every tool; sanitized errors with the real error logged server-side.
  • Fair-use rate limits per caller: 60 requests/minute, 900/hour, 5,000/day, returning 429 with Retry-After.
  • Tool list served at runtime by server_info so clients can detect a stale cache; after launch, new capability ships as a skill or an optional parameter, never a renamed or removed tool.

Derived metrics (labeled derived)

  • Equity share of adviser regulatory AUM: filed 13F value over the adviser's filed regulatory AUM from the closest date pair; results above 100% are reported as computed, with both dates shown.
  • Top-10 weight and Herfindahl concentration per filing.
  • Value change split into market movement versus net buying using implied prices derived from filed values and shares per CUSIP per quarter.

Site

  • Manager directory with search, period, location, form type and value filters, sorting and pagination, all held in the URL.
  • Manager drilldown pages keyed by SEC CIK, with the filed summary and adviser link shown by match confidence.
  • Adviser links in three recorded passes: cover-page CRD, SEC file number (801-), then normalized name + ZIP at lower confidence.
  • Data page with live coverage and refresh timestamps; light and dark themes.

Known limitations

  • 13F value is not assets under management: it excludes bonds, open-end mutual funds, cash, private funds and non-discretionary assets.
  • ETF and single-stock classification and ETF sponsor footprint are not yet offered; they need a verified security classification source and are not estimated.
  • Notice filers (13F-NT) report holdings through another manager, and those holdings are never attributed to the notice filer.
  • A filing can be up to 45 days old at quarter end, so the newest period appears with that lag.
  • SEC's published summary counts can differ from the position rows in the same release; both source figures are preserved.
  • Automatic quarterly refresh is scheduled but not yet verified end-to-end on the hosted runtime.

Facts as filed only. Every figure above is dated by period of report and filing date, and labeled filed or derived. Nothing here is investment, legal or compliance advice, and a filing is not an endorsement.