diff --git a/gateway/kanban_watchers.py b/gateway/kanban_watchers.py
index 14d2e43a6644..2f5137a8a84f 100644
--- a/gateway/kanban_watchers.py
+++ b/gateway/kanban_watchers.py
@@ -208,6 +208,24 @@ class GatewayKanbanWatchersMixin:
                         getattr(platform, "value", str(platform)).lower()
                         for platform in self.adapters.keys()
                     }
+                    # Widen to every platform any secondary profile has live,
+                    # not just the default profile's. This is only a coarse
+                    # pre-filter to skip claiming events for subs nobody can
+                    # possibly deliver — the precise per-profile check (via
+                    # gateway/authz_mixin.py::_authorization_adapter, which
+                    # forbids default-profile fallback) still runs at delivery
+                    # time below, rewinding the claim if it resolves to None.
+                    # Without this, a subscription owned by a secondary
+                    # profile on a platform the DEFAULT profile never
+                    # connected (e.g. beta owns discord, default doesn't) was
+                    # dropped here before ever being claimed — no rewind
+                    # applies to an unclaimed event, so it silently never
+                    # retries.
+                    for _profile_adapter_map in getattr(self, "_profile_adapters", {}).values():
+                        active_platforms.update(
+                            getattr(platform, "value", str(platform)).lower()
+                            for platform in _profile_adapter_map.keys()
+                        )
                     if not active_platforms:
                         logger.debug("kanban notifier: no connected adapters; skipping tick")
                         return deliveries
diff --git a/tests/gateway/test_kanban_notifier.py b/tests/gateway/test_kanban_notifier.py
index 6cdef9b85c00..4657bc3c1766 100644
--- a/tests/gateway/test_kanban_notifier.py
+++ b/tests/gateway/test_kanban_notifier.py
@@ -416,6 +416,55 @@ def test_notifier_owning_profile_adapter_no_default_fallback(tmp_path, monkeypat
     assert [ev.kind for ev in _unseen_terminal_events_for(tid, "chat-beta")] == ["completed"]
 
 
+def test_notifier_claims_platform_only_a_secondary_profile_owns(tmp_path, monkeypatch):
+    """A subscription owned by a secondary profile on a platform the DEFAULT
+    profile never connected must still be claimed and delivered.
+
+    Regression: the ``_collect()`` pre-filter built ``active_platforms``
+    solely from ``self.adapters`` (the default profile). A sub owned by
+    profile "beta" on "discord", where beta genuinely has a live discord
+    adapter but the default profile has no discord adapter at all, was
+    dropped by that pre-filter (``platform not in active_platforms``)
+    before ``claim_unseen_events_for_sub`` ever ran — unlike the
+    disconnected-adapter path, an unclaimed event is never rewound, so this
+    was a permanent, silent notification loss, not a retryable one. This
+    directly contradicts the feature's own purpose (routing notifications
+    via the owning profile), and is the same cross-profile-adapter-lookup
+    class the delivery-side chokepoint in
+    ``test_notifier_owning_profile_adapter_no_default_fallback`` already
+    guards — just one gate earlier.
+    """
+    db_path = tmp_path / "secondary-only-platform.db"
+    monkeypatch.setenv("HERMES_KANBAN_DB", str(db_path))
+    kb.init_db()
+
+    conn = kb.connect()
+    try:
+        tid = kb.create_task(conn, title="owned by beta on discord", assignee="worker")
+        kb.add_notify_sub(
+            conn, task_id=tid, platform="discord", chat_id="chat-beta",
+            notifier_profile="beta",
+        )
+        kb.complete_task(conn, tid, summary="done")
+    finally:
+        conn.close()
+
+    beta_adapter = RecordingAdapter()
+    runner = GatewayRunner.__new__(GatewayRunner)
+    runner._running = True
+    # Default profile has NO discord adapter at all.
+    runner.adapters = {Platform.TELEGRAM: RecordingAdapter()}
+    # Secondary profile "beta" has a live discord adapter.
+    runner._profile_adapters = {"beta": {Platform.DISCORD: beta_adapter}}
+    runner._kanban_sub_fail_counts = {}
+
+    asyncio.run(_run_one_notifier_tick(monkeypatch, runner))
+
+    assert len(beta_adapter.sent) == 1, (
+        f"beta's discord adapter should have received the notification; got {beta_adapter.sent!r}"
+    )
+
+
 def test_notifier_wakeup_uses_subscription_chat_type(tmp_path, monkeypatch):
     db_path = tmp_path / "chat-type-wakeup.db"
     monkeypatch.setenv("HERMES_KANBAN_DB", str(db_path))