diff --git a/PKHeX.Core/Game/GameUtil.cs b/PKHeX.Core/Game/GameUtil.cs
index 27558c63a..b9b71ebfd 100644
--- a/PKHeX.Core/Game/GameUtil.cs
+++ b/PKHeX.Core/Game/GameUtil.cs
@@ -25,7 +25,7 @@ namespace PKHeX.Core
         /// <summary>
         /// Most recent game ID utilized by official games.
         /// </summary>
-        public const GameVersion HighestGameID = RB - 1;
+        private const GameVersion HighestGameID = RB - 1;
 
         /// <summary>Determines the Version Grouping of an input Version ID</summary>
         /// <param name="version">Version of which to determine the group</param>
diff --git a/PKHeX.Core/Legality/Tables/Tables1.cs b/PKHeX.Core/Legality/Tables/Tables1.cs
index 049cb238b..472d6e395 100644
--- a/PKHeX.Core/Legality/Tables/Tables1.cs
+++ b/PKHeX.Core/Legality/Tables/Tables1.cs
@@ -37,7 +37,7 @@
 
         internal static bool TransferSpeciesDefaultAbilityGen1(int species)
         {
-            System.Diagnostics.Debug.Assert(species <= (uint)MaxSpeciesID_1);
+            System.Diagnostics.Debug.Assert((uint)species <= MaxSpeciesID_1);
             return species is (int)Species.Gastly or (int)Species.Haunter or (int)Species.Gengar
                 or (int)Species.Koffing or (int)Species.Weezing
                 or (int)Species.Mew;
diff --git a/PKHeX.Core/Legality/Verifiers/HistoryVerifier.cs b/PKHeX.Core/Legality/Verifiers/HistoryVerifier.cs
index 711601b48..4d2426e47 100644
--- a/PKHeX.Core/Legality/Verifiers/HistoryVerifier.cs
+++ b/PKHeX.Core/Legality/Verifiers/HistoryVerifier.cs
@@ -172,16 +172,23 @@ namespace PKHeX.Core
         // ORAS contests mistakenly apply 20 affection to the OT instead of the current handler's value
         private static bool IsInvalidContestAffection(IAffection pkm) => pkm.OT_Affection != 255 && pkm.OT_Affection % 20 != 0;
 
-        public static bool GetCanOTHandle(IEncounterable enc, PKM pkm, int generation) => generation < 6 || enc switch
+        public static bool GetCanOTHandle(IEncounterable enc, PKM pkm, int generation)
         {
-            EncounterTrade => false,
-            EncounterSlot8GO => false,
-            WC6 wc6 when wc6.OT_Name.Length > 0 => false,
-            WC7 wc7 when wc7.OT_Name.Length > 0 && wc7.TID != 18075 => false, // Ash Pikachu QR Gift doesn't set Current Handler
-            WC8 wc8 when wc8.GetHasOT(pkm.Language) => false,
-            WC8 {IsHOMEGift: true} => false,
-            _ => true
-        };
+            // Handlers introduced in Generation 6. OT Handling was always the case for Generation 3-5 data.
+            if (generation < 6)
+                return generation >= 3;
+
+            return enc switch
+            {
+                EncounterTrade => false,
+                EncounterSlot8GO => false,
+                WC6 wc6 when wc6.OT_Name.Length > 0 => false,
+                WC7 wc7 when wc7.OT_Name.Length > 0 && wc7.TID != 18075 => false, // Ash Pikachu QR Gift doesn't set Current Handler
+                WC8 wc8 when wc8.GetHasOT(pkm.Language) => false,
+                WC8 {IsHOMEGift: true} => false,
+                _ => true
+            };
+        }
 
         private static int GetBaseFriendship(int generation, int species, int form) => generation switch
         {