diff --git a/src/ZB.MOM.WW.ScadaBridge.Transport/Import/BundleUnlockRateLimitedException.cs b/src/ZB.MOM.WW.ScadaBridge.Transport/Import/BundleUnlockRateLimitedException.cs
deleted file mode 100644
index 3e8bd70f..00000000
--- a/src/ZB.MOM.WW.ScadaBridge.Transport/Import/BundleUnlockRateLimitedException.cs
+++ /dev/null
@@ -1,35 +0,0 @@
-namespace ZB.MOM.WW.ScadaBridge.Transport.Import;
-
-/// <summary>
-/// Thrown by <see cref="BundleImporter.LoadAsync"/> when the caller
-/// has exceeded the configured per-IP-per-hour unlock attempt cap
-/// (<see cref="TransportOptions.MaxUnlockAttemptsPerIpPerHour"/>). The 429-equivalent
-/// signal: the caller must wait for the trailing-hour window to roll forward before
-/// another passphrase attempt is accepted.
-/// </summary>
-public sealed class BundleUnlockRateLimitedException : Exception
-{
-    /// <summary>
-    /// Rate-limit key the limiter rejected the attempt against — the caller IP when
-    /// supplied, or the bundle's content hash as the architectural fallback (the
-    /// importer has no <c>IHttpContext</c> dependency by design).
-    /// </summary>
-    public string ClientKey { get; }
-
-    /// <summary>Per-window cap that was reached.</summary>
-    public int Limit { get; }
-
-    /// <summary>
-    /// Initializes a new <see cref="BundleUnlockRateLimitedException"/>.
-    /// </summary>
-    /// <param name="clientKey">The rate-limit key that exceeded its budget.</param>
-    /// <param name="limit">The configured per-window cap.</param>
-    public BundleUnlockRateLimitedException(string clientKey, int limit)
-        : base(
-            $"Bundle unlock rate limit reached ({limit} attempts per hour). "
-            + "Wait for the trailing-hour window to expire before retrying.")
-    {
-        ClientKey = clientKey ?? throw new ArgumentNullException(nameof(clientKey));
-        Limit = limit;
-    }
-}