Abstract. We show that existing laboratory experiments have the potential to unveil the origin of matter by probing leptogenesis in the type-I seesaw model with three right handed neutrinos and Majorana masses in the GeV range. The baryon asymmetry is generated by CP-violating flavour oscillations during the production of the right-handed neutrinos. In contrast to the case with only two right handed neutrinos, no degeneracy in the Majorana masses is required. The right-handed neutrinos can be found in meson decays at BELLE II, LHCb or the proposed SHiP experiment.