Under the STOCK Act, members of the US Congress have to publicly disclose their stock trades. That data is public — but it's locked in PDF filings, and most people never see it because nobody's turned it into something queryable. A few tools do serve this data as structured output.
Source: [Dev.to](https://dev.to/fatihbuilds/congressional-trading-data-as-an-api-comparing-pay-per-use-vs-subscription-3cdk)