In this talk, we investigate the molecular nature of the $D_{s0}^{*}(2317)^+$ resonance in the weak decay of the $B_c$ meson to $ J/\psi DK$. In this process, the heavy meson $B_c$ first decays into the quark pair $c\bar{s}$ via weak interaction and then the quark
pair hadronizes into final meson states. The $D_{s0}^{*}(2317)^+$ resonance is dynamically generated in the final state interaction. We describe this interaction using the chiral unitary approach. Finally, we compute the $KD$ invariant mass distribution of the decay $B_c\to J/\psi DK$ and we learn about the
nature of the $D_{s0}^{*}(2317)^+$.