The potential problem of too many unique protocol independent multicast (PIM) joins (corresponding to unique (Source, Group) combinations) in PIM join/prune messages being received by a router may be solved by controlling (e.g., limiting) a number of unique PIM joins to be sent to the router from a downstream device. This may be accomplished, for example, by communicating a limit (or multiple different limits) from a PIM device to one or more downstream PIM neighbors. For example, the limit may be encoded in a PIM Hello message (e.g., as an Option Type-Length-Value (TLV)).