luoto
In all cases I know of, you have to supply everything to your employer (licence, logbook, certificates, passport, work-permit, criminal record check etc). If you hold an ICAO licence but not from the state of your employer (e.g. an American working in an EU JAR state), you will also have to get your American licence "validated" for the EU state which also means handing over your entire paper trail to the authority in order that they can issue you with a certificate of validation.
If you are a JAR licence holder going to work in another JAR state there is no authority checking, but the employer is still obliged to check as they must ensure a pilot is fit for purpose.
RIX