13F Insight

Data & Methodology

Every number on 13F Insight traces back to a public SEC filing. This page explains where the data comes from, how we process it, and where its limits are.

Sources

All primary data is ingested directly from SEC EDGAR: Form 13F-HR quarterly institutional holdings (plus 13F-NT notices and 13F-HR/A amendments), Schedule 13D/13G beneficial-ownership filings, and Form 4 insider transactions. We do not source holdings from third-party aggregators.

380K+
13F-HR filings (1999–present)
480K+
13D/G filings (since 1994)
4.37M+
Form 4 transactions (since 2003)
30K+
Institutional filers tracked

Ingestion cadence

Dedicated workers poll EDGAR every 15 minutes for each filing family (13F, 13D/G, and Form 4 on staggered schedules), so new filings typically appear on the site within minutes of EDGAR dissemination. Derived metrics — quarter-over-quarter position changes, institutional ownership rollups, and WhaleScore — are recomputed on their own schedules after new filings land.

Processing & normalization

  • Amendment handling. 13F-HR/A restatements replace the original quarter's holdings; supplemental amendments are merged on top. Every quarter view is amendment-adjusted.
  • Identifier normalization. CUSIPs are normalized (case, zero-padding) and mapped to tickers and issuers; securities are classified by type (common stock, ETF, ADR, derivatives) so ownership rollups compare like with like.
  • Filer classification. Passive index managers, market makers, and custodians are flagged and excluded from "smart money" signal surfaces — their 13F activity reflects mandates and hedged inventory, not investment conviction.
  • Editorial analysis. AI-assisted summaries on filer, stock, and insider pages are written against the underlying filing data and reviewed before publication; each states the quarter it covers.

Known limitations

  • The 45-day lag. Managers may file up to 45 days after quarter end, so holdings are a snapshot of the past quarter, not current positions.
  • Long-only, U.S.-listed. 13F excludes shorts, cash, bonds, and most non-U.S. listings; a manager's true exposure can differ materially.
  • $100M threshold. Only managers with $100M+ in 13F securities must file, so smaller funds are absent.
  • EDGAR history. Electronic filings begin in the mid-1990s; pre-1993 data does not exist on EDGAR.

Citing our data

Cite the page URL plus the data-as-of quarter shown on the page — for example: "Berkshire Hathaway Q1 2026 13F holdings, via 13finsight.com". Machine readers can start from /llms.txt for site structure; article pages also serve a markdown variant for AI consumption.