Grant Thornton's note on German documentation rules illustrates a European pattern: tax authorities are shortening deadlines and expecting transfer pricing files to be available on request rather than assembled after an audit letter arrives, with sharper sanctions for late or thin documentation.
Dutch entities in international groups should take the hint even where local thresholds spare them. If you invoice a foreign sister company, the arm's-length story behind that price, the agreement, the method, the numbers, should exist in the file now. Reconstructing intercompany logic three years later is expensive; writing it down as you go is not.