Do you know any financial data APIs supporting signed HTTP exchanges (SXG), JOSE/JWS/JWE or any other digitally signed format to provide verified financial data (stock market data)?
The following researches gave no answer:
- HTTPS responses can't be used as signed messages because TLS doesn't provide non-repudiation.
- Kraken provides PGP public key but it's only used to sign official email correspondence.
