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HowShorted

Methodology

This page documents exactly what our data is, where it comes from, and what we do to it. If anything here and a regulator's own documentation ever disagree, the regulator is right and we have a bug; tell us.

Sources

Every figure comes from an official regulator's or self-regulatory organisation's public disclosure:FINRA and SEC EDGAR for the United States, the FCA for the UK (next section), ASIC for Australia, and the AMF, the Netherlands' AFM, Norway's Finanstilsynet, Sweden's Finansinspektionen, Spain's CNMV, Finland's Finanssivalvonta, Denmark's Finanstilsynet, Belgium's FSMA and Poland's KNF for France, the Netherlands, Norway, Sweden, Spain, Finland, Denmark, Belgium and Poland. Nothing else feeds the site.

United States

US data joins two official sources. Short interest comes from FINRA's consolidated equity short interest report: FINRA member firms must report their short positions in all US equities twice a month, for settlement on the 15th and the last business day of each month, and FINRA publishes the consolidated shares-short figure per security about nine business days after each settlement date. Shares outstanding come from SEC EDGAR: the cover-page share count of each company's latest 10-Q/10-K (or, for a US-based foreign private issuer such as Webull, its annual 20-F), always dated on or before the settlement date and never more than nine months old. Symbols are matched against dated snapshots of the SEC's ticker file, so each settlement resolves tickers as they were assigned at the time: a company that has since delisted keeps its history under an era-marked identity (its page notes the delisting year), a renamed ticker's history follows the company (Meta's FB era sits on the META page), and a recycled ticker never mixes two companies' figures.

Days to cover is FINRA's own precomputed figure from the same report: reported shares short divided by the stock's average daily trading volume, expressing the position in days of typical trading. We publish FINRA's number exactly as released and compute nothing from volume ourselves; it is the one figure on this site that involves trading volume, shown because FINRA publishes it in the same free file as the short counts. Like short interest itself, it describes size, not direction, and predicts nothing.

Fails to deliver come from the SEC's own fails-to-deliver data, a public-domain file published twice a month. For each security and settlement date it gives the aggregate net balance of shares that failed to be delivered: a balance outstanding on that date, not the number that failed that day. We show the SEC's share count exactly as published for the trailing thirteen months, beside the short interest it is often searched with, and compute nothing from it. The file also carries a closing price, which we never read or store. A fail has many ordinary causes (a late delivery, a mismatch, a corporate action), the SEC states that it cannot guarantee the accuracy of the data, and a balance says nothing about who failed or why. Months the SEC has not published simply show no figure.

US company charts also mark filing events from SEC EDGAR's submissions index: the dates a company's quarterly or annual report was filed, and the dates of 8-K filings announcing results (usually the earnings-call day). These are factual event dates shown for context, not signals, and only historical filings appear; upcoming earnings dates are not published here. The percentage we publish is FINRA's shares short divided by that share count, and both source figures are stored alongside every data point. A company with several classes of common stock (Alphabet, Meta, Ford) appears once, under its primary listed class, and its denominator is the total common shares outstanding across all classes as stated on the same cover page.

We only publish a percentage we can stand behind, so the US section excludes: over-the-counter securities and ETPs (NYSE, Nasdaq and NYSE American corporate listings only), securities with no matching SEC filer, no fresh share count or only a single one on record (recent IPOs), American depositary shares (see below), a company's secondary lines (preferred shares, notes and second share classes; the company's figure lives on its primary line), stocks in a stock split whose post-split share count has not yet appeared in an SEC filing, and any computed value above 100%, which almost always indicates a faulty denominator rather than a real position. Once a settlement date is published, its denominator is frozen: a revision marker on a US figure always means FINRA itself re-published the number.

Companies based outside the US. Many foreign companies trade in the US as American depositary shares, where one ADS can stand for several of the company's actual shares. FINRA counts short ADSs while the company's filings count its own shares, and the ratio between them is not published in any free source we can rely on, so dividing one by the other would produce a made-up percentage. Those lines are excluded. A foreign company that lists itsordinary shares directly, as IREN, Alcon, Amcor and Alkermes do, has no such ratio: both figures count the same thing, so it is ranked exactly like a US company. Where such a company is also listed on its home exchange, the percentage covers short positions reported to FINRA against the company's total shares outstanding, so it describes the US side of the book and reads low rather than high.

Share counts are checked before they are used. SEC filings occasionally carry a wrong share count: a dropped digit, one share class tagged as the company total, a figure a million times too large. An audit of our own history (September 2026) found these producing "record" percentages, so four guards now apply. A count that sits three times away from both the filing before it and the filing after it is never used; the newest count, which nothing can bracket yet, is held back when it moves like that while the short position did not (a split moves both); any computed percentage of 40% or more is checked against the filing's own cover page, where a total across share classes replaces a single-class figure; and a FINRA line only publishes under a company whose SEC registrant name it plausibly carries, which stops a fund that reused a delisted company's ticker from appearing as that company. A company held back by a guard simply shows no figure for those settlement dates rather than a wrong one. The full history was recomputed under these rules on 10 September 2026 (see the site changelog in the repository).

US short interest data: FINRA (finra.org). FINRA® is a registered trademark of the Financial Industry Regulatory Authority, Inc. This site is not affiliated with or endorsed by FINRA or the SEC. FINRA data is displayed for personal reference; bulk redistribution is not permitted (see terms).

United Kingdom

The UK source is the FCA's public short-selling disclosures under the Short Selling Regulations 2025:

UK company pages also show a pre-2026 named-aggregate series, reconstructed from our frozen archive of the FCA's old named register: at each disclosure date, the sum of the individually disclosed positions of 0.5% or more prevailing at that date. It is a lower bound on the short interest of its day, because positions between 0.1% and 0.5% were reported to the FCA but never published, and it uses a different threshold than today's ANSP, so the two series are charted separately and are not comparable point for point. The reconstruction is frozen: it ends on 10 July 2026 and never updates.

We hold no market-data licences by design: no share prices, market caps or volumes appear anywhere on this site, only regulatory position data.

Timing

The FCA publishes each working day at approximately 12:00 UK time, two working days after the position date (T+2). Our pipeline ingests at 12:30 UK with retries at 14:00 and 17:00. If a publication is missing all day, the site keeps the previous day's data and the homepage timestamp keeps showing the last real update, currently 13 Oct 2026.

Validation

Every downloaded file must pass validation before anything is published: the file parses; the row count is plausible against recent days; every ANSP value is within 0–100%; ISINs are well-formed; dates parse and are not in the future; no duplicate company/date rows. If any check fails we publish nothing and keep yesterday's data: accuracy over availability, always. Companies appearing in the publication but not on the RSL are kept and flagged, never silently dropped.

Corrections and revised figures

The FCA may exclude a notified position while verifying it and may amend or re-publish previously published aggregates. Corrections are a normal part of this dataset, and we treat them explicitly:

Derived numbers

Rankings, 1d/5d/20d changes, sparklines, the new & leaving lists, the sector and weekly digest pages, the all-time records and the embeddable charts are computed from the archived publications, nothing else. Changes are percentage-point moves measured across published trading days (published reports for the US); companies with insufficient history show "–". Company URLs are stable slugs; a renamed issuer keeps its URL.

The legacy archive (pre-2026 register)

Before 13 July 2026 the UK published individually named short positions at the 0.5% threshold. We archived that register's final state (every current and historical disclosure back to 2012) before it was switched off. It powers the transition story and is kept frozen; it is not part of the daily dataset.

Australia

Australian data comes from ASIC's daily aggregated short position reports: for each ASX-quoted product, the short positions reported to ASIC by all short sellers (reporting obligations begin at A$100,000 or 0.01% of capital) as a percentage of total product in issue. ASIC publishes each trade date's file on the fourth business day after it (T+4); we ingest it the day it appears and never recompute ASIC's percentages. ASIC notes it cannot verify every individual report. The file covers all quoted products, occasionally including ETPs and quoted debt where reported positions can exceed 100% of a stub's units on issue.

Short position data © Australian Securities & Investments Commission. Reproduced with permission under CC BY 4.0.

Europe (France, Netherlands, Norway, Sweden, Spain, Finland, Denmark, Belgium, Poland)

European data comes from each national regulator's public register of named net short positions under the EU Short Selling Regulation: individual positions of 0.5% or more of share capital, with the position holder identified. We aggregate those disclosures per company per trading day (the aggregate is a floor: positions between 0.1% and 0.5% are reported privately and are not public) and list the current named holders on each company page.

What we are not

Independent site. Not affiliated with FINRA, the SEC, the FCA, ASIC, AMF, AFM, Finanstilsynet, Finansinspektionen, CNMV, the FSMA, the KNF or any other regulator. Nothing here is investment advice: we publish and explain regulatory data; we do not interpret it into recommendations, predictions or "signals". Internal operational notes: UK clock changes shift the FCA's publication time relative to UTC; our schedule is reviewed at each change.