[en] A wide class of neutrino physics motivated models are characterized by the spontaneous violation of a global U(1) lepton number symmetry at or below the electroweak scale by an SU(2)xU(1) singlet vacuum expectation value <σ>< or ∼O(1) TeV. In all these models the main Higgs decay channel is likely to be 'invisible', e.g. h→JJ, where J denotes the associated weakly interacting pseudoscalar Goldstone boson - the majoron. This leads to events with large missing energy that could be observable at LEP and affect the Higgs mass bounds obtained, as well as lead to novel ways to search for Higgs bosons and high-energy supercolliders such as the LHC/SSC. (orig.)