The invention relates to the field of the protection of security documents such as for example banknotes and identity documents against counterfeit and illegal reproduction. In particular, the presentinvention provides processes for magnetically transferring one or more indicia into a not yet hardened coating layer made of a coating composition comprising platelet-shaped magnetic or magnetizablepigment particles so as to produce optical effect layers (OELs) as anti-counterfeit means on security documents or security articles or for decorative purposes.