This paper provides a TU alpha-core existence result in a large class of no
rmal form games. In the oligopoly markets of a homogeneous good, the TU alp
ha-core is non-empty if all profit functions are continuous and concave. In
a general game, the existence of TU alpha-core follows from the weak separ
ability, the compactness and convexity of choice sets, and the concavity an
d continuity of payoff functions.