diff --git a/Nautilus/Handlers/KnownTechHandler.cs b/Nautilus/Handlers/KnownTechHandler.cs
index 8b3e1ca38..afc0acb98 100644
--- a/Nautilus/Handlers/KnownTechHandler.cs
+++ b/Nautilus/Handlers/KnownTechHandler.cs
@@ -336,6 +336,21 @@ public static void RemoveAllCurrentAnalysisTechEntry(TechType targetTechType)
         RemoveAnalysisTechEntry(targetTechType);
     }
 
+    /// <summary>
+    /// Allows you to remove a <see cref="TechType"/> from being unlocked by default.
+    /// </summary>
+    /// <param name="techType"></param>
+    public static void RemoveDefaultUnlock(TechType techType)
+    {
+        var modName = ReflectionHelper.CallingAssemblyByStackTrace().GetName().Name;
+        if (!KnownTechPatcher.DefaultRemovalTechs.TryGetValue(modName, out var techTypes))
+            techTypes = new List<TechType>();
+        techTypes.Add(techType);
+
+        KnownTechPatcher.DefaultRemovalTechs[modName] = techTypes;
+        Reinitialize();
+    }
+
     /// <summary>
     /// References to generic unlock sounds and unlock messages for the Known Tech system, matching those used in the base game.
     /// </summary>
diff --git a/Nautilus/Patchers/KnownTechPatcher.cs b/Nautilus/Patchers/KnownTechPatcher.cs
index 0fc44187c..f9fec628f 100644
--- a/Nautilus/Patchers/KnownTechPatcher.cs
+++ b/Nautilus/Patchers/KnownTechPatcher.cs
@@ -14,6 +14,7 @@ internal class KnownTechPatcher
     internal static HashSet<TechType> LockedWithNoUnlocks = new();
     internal static HashSet<TechType> HardLocked = new();
     internal static HashSet<TechType> RemovalTechs = new();
+    internal static Dictionary<string, List<TechType>> DefaultRemovalTechs = new();
     internal static IDictionary<TechType, KnownTech.AnalysisTech> AnalysisTech = new SelfCheckingDictionary<TechType, KnownTech.AnalysisTech>("AnalysisTech", AsStringFunction);
     internal static IDictionary<TechType, List<TechType>> BlueprintRequirements = new SelfCheckingDictionary<TechType, List<TechType>>("BlueprintRequirements", AsStringFunction);
     internal static IDictionary<TechType, KnownTech.CompoundTech> CompoundTech = new SelfCheckingDictionary<TechType, KnownTech.CompoundTech>("CompoundTech", AsStringFunction);
@@ -49,7 +50,25 @@ internal static void Reinitialize()
 
     private static void InitializePrefix(PDAData data)
     {
-        data.defaultTech.AddRange(UnlockedAtStart);
+        foreach (var unlockedTech in UnlockedAtStart)
+        {
+            if (!data.defaultTech.Contains(unlockedTech))
+            {
+                data.defaultTech.Add(unlockedTech);
+                InternalLogger.Debug($"Setting {unlockedTech.AsString()} to be unlocked at start.");
+            }
+        }
+
+        foreach (var removalTechsByMod in DefaultRemovalTechs)
+        {
+            foreach (var removalTech in removalTechsByMod.Value)
+            {
+                if (data.defaultTech.Remove(removalTech))
+                {
+                    InternalLogger.Debug($"{removalTechsByMod.Key} removed {removalTech.AsString()} from unlocking at start.");
+                }
+            }
+        }
 
         foreach (var tech in AnalysisTech.Values)
         {
@@ -80,6 +99,7 @@ private static void InitializePrefix(PDAData data)
                 continue;
             }
             
+            InternalLogger.Debug($"Adding TechTypes to be unlocked by {blueprintRequirements.Key}: {blueprintRequirements.Value.Join((techType) => techType.AsString())}");
             data.analysisTech[index].unlockTechTypes.AddRange(blueprintRequirements.Value);
         }