Violation of the disclosure principle
Sec. 1 (1) sentence 5 of the Law on Temporary Employment (AÜG, Arbeitnehmerüberlassungsgesetz) stipulates that all cases which German law defines as temporary employment must also be contractually designated as temporary employment.
If external personnel are assigned and German law defines this as temporary employment, but the parties to the contract do not designate it as such, this is then deemed to constitute so-called concealed temporary employment.
Concealed temporary employment can be punished by fines of up to €30,000. Furthermore, there is a risk that a license to operate a temporary employment agency that has already been issued will be revoked.