We evaluate the compositeness effects of leptons on the vertexW&tgr;&ngr;&tgr;in the context of an effective Lagrangian approach and get the corrections to the non universal couplingg&tgr;where we consider that only the third family is composed. We find the allowed region from the experimentalg&tgr;/gequotient for (&Lgr; versusm*) plane when the masses of the excited states of the third generation are considered equal, i.e.,m&tgr;*=m&Vthgr;&tgr;*=m*.©2001 American Institute of Physics.