Method, apparatus and computer program product for generating filter cache are described herein. For example, the apparatus includes at least one processor and at least one non-transitory memory including program code. The at least one non-transitory memory and the program code are configured to, with the at least one processor, cause the apparatus to at least generate an index document array, generate a group identifier lookup array, generate a channel identifier lookup array, and generate a filter cache for the index document array based at least on the group identifier lookup array and the channel identifier lookup array.