Since both are EU businesses, these were "Intra-Community Acquisitions"[1] so the VAT was reverse-charged.
Either way, they knew the business' VAT ID, Chamber of Commerce ID, etc. and had been billing us successfully using that info for a good while, there were no outstanding bills, and there was nothing nefarious or questionable going on our servers or with the associated traffic (just running legacy applications and services).
All in all a super weird experience, which was a shame since we were otherwise and up until then quite happy with them.
Either way, they knew the business' VAT ID, Chamber of Commerce ID, etc. and had been billing us successfully using that info for a good while, there were no outstanding bills, and there was nothing nefarious or questionable going on our servers or with the associated traffic (just running legacy applications and services).
All in all a super weird experience, which was a shame since we were otherwise and up until then quite happy with them.
[1]: https://en.wikipedia.org/wiki/European_Union_value_added_tax...