Before revision: We examine problems of "intermediated implementation . "  An example is sales, whereby retailers compete through offering consumption bundles to consumers with hidden tastes, whereas a manufacturer with a potentially different goal than retailers' can regulate only the sold goods but not the charged prices by legal barriers.
After revision: We examine problems of "intermediated implementation . " in which a single principal can only regulate limited aspects of the consumption bundles traded between intermediaries and agents with hidden characteristics. An example is sales, whereby retailers compete through offering consumption bundles to consumers with hidden tastes, whereas a manufacturer with a potentially different goal than retailers' can regulate only the sold goods but not the charged prices by legal barriers.