diff --git a/Dalamud.Bootstrap/BootstrapException.cs b/Dalamud.Bootstrap/BootstrapException.cs
index 81f8d7172..9d9c23f88 100644
--- a/Dalamud.Bootstrap/BootstrapException.cs
+++ b/Dalamud.Bootstrap/BootstrapException.cs
@@ -4,9 +4,9 @@ using System.ComponentModel;
 namespace Dalamud.Bootstrap
 {
     /// <summary>
-    /// An error that is thrown when bootstraping Dalamud failed.
+    /// An error that is thrown when there was a problem with bootstraping.
     /// </summary>
-    public class BootstrapException : Exception
+    public sealed class BootstrapException : Exception
     {
         internal BootstrapException() : base() { }
 
diff --git a/Dalamud.Bootstrap/Bootstrapper.cs b/Dalamud.Bootstrap/Bootstrapper.cs
index f39959123..6439de56a 100644
--- a/Dalamud.Bootstrap/Bootstrapper.cs
+++ b/Dalamud.Bootstrap/Bootstrapper.cs
@@ -8,7 +8,7 @@ using Dalamud.Bootstrap.SqexArg;
 
 namespace Dalamud.Bootstrap
 {
-    public class Bootstrapper
+    public sealed class Bootstrapper
     {
         private readonly BootstrapperOptions m_options;
 
diff --git a/Dalamud.Bootstrap/BootstrapperOptions.cs b/Dalamud.Bootstrap/BootstrapperOptions.cs
index 31da97457..52464a988 100644
--- a/Dalamud.Bootstrap/BootstrapperOptions.cs
+++ b/Dalamud.Bootstrap/BootstrapperOptions.cs
@@ -3,7 +3,7 @@ using System.IO;
 
 namespace Dalamud.Bootstrap
 {
-    public class BootstrapperOptions
+    public sealed class BootstrapperOptions
     {
         public static BootstrapperOptions Default => new BootstrapperOptions
         {
diff --git a/Dalamud.Bootstrap/SqexArg/SqexArgException.cs b/Dalamud.Bootstrap/SqexArg/SqexArgException.cs
index 062fd0ef0..99164896c 100644
--- a/Dalamud.Bootstrap/SqexArg/SqexArgException.cs
+++ b/Dalamud.Bootstrap/SqexArg/SqexArgException.cs
@@ -2,7 +2,7 @@ using System;
 
 namespace Dalamud.Bootstrap.SqexArg
 {    
-    public class SqexArgException : Exception
+    internal sealed class SqexArgException : Exception
     {
         public SqexArgException() { }
         public SqexArgException(string message) : base(message) { }
diff --git a/Dalamud.Bootstrap/Windows/ProcessException.cs b/Dalamud.Bootstrap/Windows/ProcessException.cs
index 5d7c426df..f93c9f95c 100644
--- a/Dalamud.Bootstrap/Windows/ProcessException.cs
+++ b/Dalamud.Bootstrap/Windows/ProcessException.cs
@@ -6,7 +6,7 @@ namespace Dalamud.Bootstrap.Windows
     /// <summary>
     /// An exception that is thrown when there was an error while interacting with the process.
     /// </summary>
-    public class ProcessException : Exception
+    internal sealed class ProcessException : Exception
     {
         public uint Pid { get; }