If the number is not correct, there should be a warning sign with a corresponding mouse-over pop-up next to the input field.
If the number is correct, there should be a green check mark instead.
In any way it must be possible to enter and save a non-austrian insurance number though.
After an insurance number (SVNR) ist entered (more specific: when the field looses focus), it should be checked, if the insurance number is correct. Here you find how to calculate the check digit: https://www.sozialversicherung.at/cdscontent/?contentid=10007.820902&viewmode=content#datareplacementdoneWorausbestehtdieVersicherungsnummer820902
If the number is not correct, there should be a warning sign with a corresponding mouse-over pop-up next to the input field. If the number is correct, there should be a green check mark instead.
In any way it must be possible to enter and save a non-austrian insurance number though.