  Separating codes have their applications in collusion-secure fingerprinting
for generic digital data, while they are also related to the other structures
including hash family, intersection code and group testing. In this paper we
study upper bounds for separating codes. First, some new upper bound for
restricted separating codes is proposed. Then we illustrate that the Upper
Bound Conjecture for separating Reed-Solomon codes inherited from Silverberg's
question holds true for almost all Reed-Solomon codes.
