https://www.nature.com/articles/srep30461 To within 0.13 %, an experiment performed at the Large Hadron Collider in 2016 has confirmed that both the inertial and gravitational mass of the positron (antimatter equivalent of an electron) is the same as that of the electron. The experiment boasts impressive accuracy, the residual 0.13% in gravitational mass differences in positrons vs. electrons attributed to differences in the proximity of Earth to the Sun during various repeat runs of the experiment. So, to anyone holding out any hope that a cryogenic vessel filled with solid antihydrogen and equipped with magnetic containment could be employed to slip the surly bonds of gravitation keeping us all pinned to the ground of this small planet, it looks as though rocket engines to accomplish the lifting will not be going away any time soon. Antimatter rocket engines may still be an efficent means of providing thrust to rocket engines already in space, but whatever goes up, be it matter or antimatter, it will still, nonetheless, eventually fall under the influence of gravitation. What is now termed the WEP (Weak Equivalence Principle) of gravitational and inertial mass first commemorated in Newton's Theory of Universal Gravitation is therefore upheld in the case of antimatter.