The integration of a participant role (especially the Trajector or Landmark for locative action verbs) or of the Instrument in the morphological substance of French verbs is a widespread phenomenon illustrated and classified in the section on denominative verb formation of J. Dubois & F. Dubois-Charlier's book devoted to suffixal derivation in French (1999). In this paper their classification is subjected to a critical investigation based on the typology of French predicate frames proposed in François (2003). Particular attention is paid to the distinction between the integration of a locative landmark, which entails a valence reduction, and that of the instrument which does not affect the verb valence, and in that particular case to the mental accessibility of the way of using the instrument and thereby to the status of the verb as a properly derived or only a complex item.