diff --git a/decnet/correlation/event_kinds.py b/decnet/correlation/event_kinds.py
index acc7bed1..0af95176 100644
--- a/decnet/correlation/event_kinds.py
+++ b/decnet/correlation/event_kinds.py
@@ -41,10 +41,6 @@ INTERACTION_EVENT_TYPES: frozenset[str] = frozenset({
     "rcpt_to",
     "rcpt_denied",
     "message_accepted",
-    # probe_forwarded fires when we actually relay the test email upstream
-    # so the attacker can verify receipt. forwarded=1 means the upstream
-    # accepted it; forwarded=0 means it failed (but the attacker still got 250).
-    "probe_forwarded",
     # File / payload activity
     "file_captured",
     "upload",