Authenticity judgments involve how individuals distinguish what appears to be real versus fake, genuine versus phony. In this investigation, we bring authenticity into the laboratory to assess it in a manner quite different from most extant approaches. Taking a Peircian semiotic view in a context of environmentally conscious consumption, we develop and test a set of hypotheses concerning the effects of indexical and iconic cues to an authentic “green” product meaning. Results suggest that effects of these indicators of authenticity can be induced in a controlled manner with products being assessed as more or less “green” on the basis of particular cue arrangements. Furthermore, the effectiveness of these semiotic cues is moderated by a basic distinction among products. Taken together, the results provide evidence supporting a meaning validation process as the basis of authenticity judgments and suggest new directions for theory building in a domain where there is substantial practitioner interest. Copyright © 2012 John Wiley & Sons, Ltd.