The Literal Meaning is “On the plaintiff rests the proving.” The burden of proof is on the plaintiff.
Anguo Jiao v Authority
23.”A Commission of the Institut de Droit International has this year stated the basic principle for international litigation in the same terms: The basic principle relating to evidence and proof is actori incumbit probatio, i.e. the claimant must prove the assertion of facts that he makes. (Annuaire de Instituted Droit International – Session de Bruges Vol 70-1 (2003) 393)”