  We study the possibility of dark matter in the form of heavy neutrinos from a
fourth lepton family with helicity suppressed couplings such that dark matter
is produced thermally via annihilations in the early Universe. We present all
possible constraints for this scenario coming from LHC and collider physics,
underground direct detectors, neutrino telescopes, and indirect astrophysical
searches. Although we embed the WIMP candidate within a model of composite
dynamics, the majority of our results are model independent and applicable to
all models where heavy neutrinos with suppressed couplings account for the dark
matter abundance.
