diff --git a/zone/mob.cpp b/zone/mob.cpp
index 590751bd0..7dcbbcb15 100644
--- a/zone/mob.cpp
+++ b/zone/mob.cpp
@@ -990,7 +990,7 @@ void Mob::CreateSpawnPacket(EQApplicationPacket* app, NewSpawn_Struct* ns) {
 	strcpy(ns2->spawn.name, ns->spawn.name);
 
 	// Set default Last Names for certain Classes if not defined
-	if (strlen(ns->spawn.lastName) == 0)
+	if (RuleB(NPC, UseClassAsLastName) && strlen(ns->spawn.lastName) == 0)
 	{
 		switch (ns->spawn.class_)
 		{