[en] A minimal set of genuine four-coupling operators between vector bosons is derived which have no connection to the standard parametrisation of the trilinear anomalous W couplings. A global weak SU(2) symmetry and, for those operators where photons are involved, a local U(1)_QED is imposed. These requirements are strong enough to forbid or highly suppress any contribution to weak vector bosons self energies. Tests of these couplings are then only possible at high energies. The effects of these couplings are studied at the NLC(500 GeV) in all possible three vector bosons production: e⁺e^- → W⁺W^-Z, ZZZ, W⁺W^-γ, ZZγ and Zγγ. The possibility of having polarised beams is considered and the usefulness of looking at particular distributions is pointed out. (R.P.) 16 refs., 8 figs