A method is illustrated for minimizing the number of internal states in incompletely specified sequential networks. The starting point for minimizing technique in this paper is the set of maximal compatibility classes which covers the original flow table and the minimal covering can be obtained directly by employing three rules. The reduction techniques for prime implicant table or covering and closure table are not employed in this paper. Although the minimizing technique is applied to some specific problems, it is believed that the concepts are general in nature and can be applied to any type of incompletely specified flow tables.