diff --git a/common/spdat.h b/common/spdat.h
index e44bf8e08..c82d95b74 100644
--- a/common/spdat.h
+++ b/common/spdat.h
@@ -735,7 +735,7 @@ struct SPDat_Spell_Struct
 /* 180 */	int spell_category; // -- GLOBAL_GROUP
 /* 181 */	//int pvp_duration; // buffdurationformula for PvP -- PVP_DURATION
 /* 182 */	//int pvp_duration_cap; // buffduration for PvP -- PVP_DURATION_CAP
-/* 183 */	//int pcnpc_only_flag; // valid values are 0, 1, and 2 -- PCNPC_ONLY_FLAG
+/* 183 */	//int pcnpc_only_flag; // valid values are 0, 1 = PCs (and mercs), and 2 = NPCs (and not mercs) -- PCNPC_ONLY_FLAG
 /* 184 */	bool cast_not_standing; // this is checked in the client's EQ_Spell::IsCastWhileInvisSpell, this also blocks SE_InterruptCasting from affecting this spell -- CAST_NOT_STANDING
 /* 185 */	bool can_mgb; // 0=no, -1 or 1 = yes -- CAN_MGB
 /* 186 */	int dispel_flag; // -- NO_DISPELL