Hello,
this idea is a suggestion for a ungarian data source. The source is been used by our customer Schwarz to verify ungarian TAX Numbers and VAT´s.
They also shared a document with us about the provider .
The page is operated by a consulting company (https://www.systemfox.com/de/start/), but on page 5 of the document (NAV REST-client implementations) it looks like the data source they are using, is a official govermental one(https://nav.gov.hu/en).
Implement "vanenav.net/vatcheck" as a Data Source for for Hungarian TAX Numbers and BP Information
Merged