Where the data comes from, and what may be shown
The binding constraint on a site like this is not the price of market data. It is the licence attached to it. Almost every affordable API tier is contractually personal, non-commercial and internal-use only, and several explicitly forbid public display.
Two flags, deliberately separate
May the raw values from this source be displayed publicly, verbatim? For most paid feeds the answer is no.
May statistics computed from it be displayed? Our own paper fills, percentage returns, profit and loss, drawdown and rank are our work product, not licensed market data. This distinction is what makes the project affordable at all — the alternative display-licensed tier costs about $2,499 a month.
The licence is not a comment in a README. It is a runtime object attached to every provider, the publication path asserts on it, and the build refuses to produce a deployable payload if an unpublishable source reaches it. Getting this wrong is made loud rather than silent.
Sources used to build this site
| Source | Vendor | Raw | Derived | Verified |
|---|---|---|---|---|
| aiport_own_work | aiport (this platform) own-work-product | publishable | yes | 2026-08-06 |
| sec_edgar | U.S. Securities and Exchange Commission public | publishable | yes | 2026-08-06 |
Notes on each source, including the ones deliberately not used, are in the licence register in the repository. The register records rejected vendors too, so that nobody re-evaluates them from scratch a year later.
Why you will not see a CUSIP anywhere on this site
13F filings are keyed by CUSIP. CUSIP is licensed by CUSIP Global Services with active enforcement, and its copyrightability is unresolved in two class actions in the Southern District of New York. Republishing them would be the clearest legal trap in this project.
The solution is structural rather than procedural. OpenFIGI maps CUSIP to a ticker and a FIGI; FIGI is an open standard and freely redistributable. No database table here has a CUSIP column, the public representation of an instrument has no field for one, and the pre-deploy check scans both the payload and this site's own source for a CUSIP field or property access. A CUSIP is held transiently in memory during the 13F join and never persisted.
Prices are the hard part, and are not solved yet
Raw price bars older than 24 hours need no exchange licence, which is why this site is designed around T+1 charts. Fresher data needs a display licence. Until one is contracted, no price series appears here at all — and the pre-deploy check looks for rendered OHLC objects by their shape, so a price chart cannot arrive quietly.
Macro series are checked individually rather than as a group. The aggregator used for them is a redistributor whose own terms are permissive, but the terms of the series it hosts are not uniformly so: some are third-party copyrighted and must never reach a public surface. A series with no recorded licence status is treated as forbidden, and the assertion enforces that rather than trusting a convention.
News
Headline, publisher and outbound link only. Article body text is the publisher's copyright and not the aggregator's to grant; most aggregator licences forbid storing it and separately forbid feeding it to a language model. Regulatory filings and issuer investor-relations pages are the exceptions, and are used in full.