  The recent discovery, by the LHCb collaboration, of the $\Xi_{cc}^{++}$
doubly charmed baryon, has renewed interest in the spectroscopy of doubly heavy
hadrons. Experimentally, however, searches for such states appear highly
challenging. The reconstructed final states tend to involve multiple heavy
flavoured (beauty or charm) hadrons, so the yield for any exclusive decay mode
will be suppressed to unobservably low levels by the product of several
branching fractions, each of which is typically $10^{-3}$--$10^{-2}$. Noting
that decays of double beauty hadrons are the only possible source of $B_c^-$
mesons that are displaced from the primary vertices of proton-proton collisions
at the LHC, a more promising inclusive search strategy is proposed.
