About OverlapCheck

OverlapCheck turns fund holdings and options positioning into answers an investor can inspect: what the funds actually own, where exposures repeat, and how market positioning changes. The tools are informational and do not recommend trades.

Where the data comes from

ETF holdings come from official issuer files and SEC filings. Options pages use end-of-day open interest and quote data. Every data page shows the applicable source date; different issuers publish on different schedules, so two funds can have different dates.

How the analysis is produced

Pairwise overlap is calculated by matching shared securities and summing the smaller portfolio weight for each match. Portfolio look-through multiplies each fund holding by the amount allocated to that fund, then combines identical securities. The formulas, limitations, and sector-classification rules are documented in our methodology.

Editorial standards

We distinguish measured data from interpretation, show dates next to time-sensitive figures, and avoid presenting max pain or gamma exposure as predictions. When a source is delayed or a method has a known limitation, the relevant page says so. Material template and guide changes use a fixed, reviewable update date rather than changing on every build.

Scope and corrections

Coverage currently focuses on selected US-listed ETFs and liquid US options products. OverlapCheck is not a broker, adviser, tax professional, or substitute for issuer records. If a displayed figure disagrees with an issuer file, verify the issuer record before acting and send the affected URL to overlapcheck@agentmail.to.