A method and an apparatus (10) for generating a three-dimensional work piece containing an information code are provided. The method comprises the steps of applying a raw material powder (18) onto a carrier (14) by means of a powder application device (16), irradiating electromagnetic or particle radiation (22) onto the raw material powder (18) applied onto the carrier (14) by means of an irradiation device (20), and controlling the operation of the powder application device (16) and the irradiation device (20) so as to generate an information code pattern (36) on or in the work piece (12), wherein the information code pattern (36) is defined by the microstructure (34) of the work piece (12).