Will the relativistic kinematics increase the number of stable multiquarks?
Few stable multiquarks remain once a careful treatment of the few-body problem is implemented. In this contribution we consider the role played by relativistic kinetic energy on their stability. It is found that the binding energy is lower in the relativistic case. Tetraquarks with double heavy flavor become stable for a larger heavy-light mass ratio. All-heavy tetraquarks, not stable in standard quark models, remain unstable when a relativistic form of kinetic energy is adopted.