X (3872) tetraquarks in B and Bs decays

We discuss how the latest data on X(3872) in B and Bs decays speak about its tetraquark nature. The established decay pattern, including the up-to-date observations by CMS, are explained by the mixing of two quasidegenerate, unresolvable neutral states. The same mechanism also explains isospin violations in X decays and strongly suggests that the lurking charged partners are required to have very small branching fractions in J/ψρ±, well below the current experimental limits. In addition, a new prediction on the decay into J/ψω final states is attained. The newest experimental observations are found to give thrust to the simplest tetraquark picture and call for a definitive, in-depth study of final states with charged ρ mesons.