Following Ann. Appl. Probab.
9 (1999) 904--950
we continue the study of the problem of
expected utility maximization in incomplete markets. Our goal is to
find minimal conditions on a model and a utility function for
the validity of several key assertions of the theory to hold true.
In the previous paper we proved that a minimal condition on the
utility function alone, that is, a minimal market
independent condition, is that the asymptotic elasticity of the
utility function is strictly less than 1. In this paper we show that
a necessary and sufficient condition on both, the
utility function and the model, is that the value function of the
dual problem is finite.