US short interest, explained

The United States has the world's most-watched stock market but no daily official short-selling disclosure. What it has instead is a twice-monthly census: broker-dealers that are FINRA members must report the short positions held in their accounts for every US equity, and FINRA publishes the consolidated total per stock. That number, not an estimate or a model, is what our US league table shows.

The cadence: settlement dates, not calendar days

Positions are counted as of two settlement dates each month: the 15th and the last business day (each rolled back to the preceding business day when it falls on a weekend or holiday). Firms then have two business days to report, and FINRA disseminates the consolidated figures about seven business days after that, roughly nine business days after settlement. Each update you see here is therefore a snapshot around two weeks old on arrival. That lag is set by regulation, and it is the same for everyone, including professional data vendors.

Official figure vs daily estimates

Search for a ticker's short interest and you will find sites showing daily numbers. Those are estimates, usually blends of exchange short-sale volume, securities-lending data and proprietary models, and they routinely disagree with each other and with FINRA. We publish the official consolidated report only: it is slower, but it is the number the market is actually required to report, and every figure on our pages can be traced to a specific FINRA file.

How we compute the percentage

FINRA reports shares short. To make US stocks comparable with our other markets (the UK's percentage of issued share capital, Australia's percentage of units on issue), we divide by each company's shares outstanding from the cover page of its latest SEC filing (10-Q or 10-K, via EDGAR, always dated on or before the settlement date). Where no trustworthy denominator exists, as with ETFs and funds, stale filers, or companies listed under several share classes, we exclude the stock rather than publish a misleading percentage. The exact rules are on the methodology page.

Revisions

FINRA occasionally re-publishes a settlement date's file with corrected figures. When that happens we update the number, keep the old value in our archive, and mark the data point with a ʳ. See how revisions work.

Frequently asked questions

Why does the US number update only twice a month?

FINRA Rule 4560 requires member firms to report short positions for settlement on the 15th and the last business day of each month. FINRA publishes the consolidated totals about nine business days after each settlement date. No daily official figure exists.

Why is this different from the short interest on estimate sites?

Many popular sites show daily estimates blended from exchange data, borrow rates and their own models. We show only the official consolidated number that broker-dealers are required to report to FINRA, on FINRA's calendar.

What does % of shares outstanding mean?

We divide FINRA's reported shares short by the company's total shares outstanding, taken from the cover page of its latest SEC filing. It is the same style of figure as the UK's and Australia's official percentages, so markets can be compared like for like.

Why are some stocks missing?

We only publish a percentage we can stand behind. ETFs and funds, stocks with no fresh SEC share count, and multi-class listings (where one company trades under several tickers) are excluded from rankings rather than shown with a misleading denominator.