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How to read the documents these pages are built from — and, more often, what those documents do not say.
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14 articles- How a 13F works, and why it is history
A 13F lists the covered U.S. equity positions a large manager held on the last day of a quarter, filed up to forty-five days later. It is a photograph of a past date with several categories missing, not a portfolio.
Updated 2026-07-26
- How additions and removals are worked out
Sanctions lists are published as complete files, not as streams of changes. The only way to know that someone was added or removed is to compare two complete versions, and the integrity of that comparison decides whether the result is meaningful.
Updated 2026-07-26
- How to check any figure here against the original document
Every record carries the identifiers needed to find the document it came from. Nothing on this site is meant to be taken on trust, and when our reading disagrees with the filing, the filing is right.
Updated 2026-07-26
- How to read XBRL, and why the tags differ
Tagging makes the numbers in a financial report machine-readable, but two companies can tag the same line differently and both be correct. The tag is part of the figure, not an implementation detail.
Updated 2026-07-26
- How to read a Form 4
A Form 4 reports a change in an insider's holdings. It has two tables, a code on every row and two different dates, and reading it as "insider bought" or "insider sold" loses most of what it says.
Updated 2026-07-26
- How to read a person's insider history
A person page collects one individual's reported transactions across every company where they are covered by insider reporting. It starts and stops on administrative dates, and the shape of the record is largely set by rules rather than by decisions.
Updated 2026-07-26
- How to read the filings calendar
The calendar records dates taken from documents, marked as confirmed or derived. Future dates are published only when a document states them, and the density of a day says as much about deadlines as about companies.
Updated 2026-07-26
- Preparing acquisition data for a tax return
The cost basis calculator adds up lots you type in and shows the working. It knows nothing about your jurisdiction, your account history or your circumstances, and it is a data preparation aid rather than a tax computation.
Updated 2026-07-26
- What disclosure lag means
Every fact in public financial data has two dates — when it happened and when it became public. The gap between them differs by form, is built into the rules, and is shown on every record here.
Updated 2026-07-26
- What the indexability threshold is
A page is published only when there is enough real data behind it to be worth reading. Below that line the address either does not exist or is closed to search engines, and no example data is ever used to fill the gap.
Updated 2026-07-26
- Why a grant is not a purchase
Both increase an insider's holdings and both appear in the same filing, but one is compensation delivered on a calendar and the other is a person spending their own money. Adding them together produces a number that means nothing.
Updated 2026-07-26
- Why a name match is not an identification
Sanctions screening compares strings. Strings are shared by strangers, spelled several valid ways and published with warnings attached. A hit is the start of the work, and an empty result is not a clearance.
Updated 2026-07-26
- Why a reference rate is not the rate you get
A central bank reference rate is a daily published benchmark for accounting and statistics. It has no bid, no ask and no obligation behind it, and it does not exist at all on days the publisher does not work.
Updated 2026-07-26
- Why an empty result is an answer
Several tools here will refuse to produce a number. That refusal is deliberate: a missing value is not a zero, an unpublished rate is not last week's rate, and no match found is not a clearance.
Updated 2026-07-26