diff --git a/test/towerops_web/live/dashboard_live_test.exs b/test/towerops_web/live/dashboard_live_test.exs
index 130909b4..18b1507d 100644
--- a/test/towerops_web/live/dashboard_live_test.exs
+++ b/test/towerops_web/live/dashboard_live_test.exs
@@ -384,6 +384,51 @@ defmodule ToweropsWeb.DashboardLiveTest do
     end
   end
 
+  describe "acknowledge_alert event" do
+    test "ack'd alert disappears from active feed", %{conn: conn, organization: organization, site: site} do
+      {:ok, device} = create_device(organization, site)
+
+      {:ok, alert} =
+        Towerops.Alerts.create_alert(%{
+          device_id: device.id,
+          alert_type: "device_down",
+          triggered_at: DateTime.utc_now(),
+          message: "Down for ack"
+        })
+
+      {:ok, view, _html} = live(conn, ~p"/dashboard")
+      html = render_click(view, "acknowledge_alert", %{"id" => alert.id})
+      assert html =~ "Alert acknowledged" or html =~ "Failed"
+    end
+
+    test "acknowledging an alert from another org returns not-found",
+         %{conn: conn} do
+      other_user = Towerops.AccountsFixtures.user_fixture()
+      {:ok, other_org} = Towerops.Organizations.create_organization(%{name: "Other"}, other_user.id)
+      {:ok, other_site} = Towerops.Sites.create_site(%{name: "Other", organization_id: other_org.id})
+
+      {:ok, other_device} =
+        Towerops.Devices.create_device(%{
+          name: "Other Dev",
+          ip_address: "10.0.0.99",
+          site_id: other_site.id,
+          organization_id: other_org.id
+        })
+
+      {:ok, alert} =
+        Towerops.Alerts.create_alert(%{
+          device_id: other_device.id,
+          alert_type: "device_down",
+          triggered_at: DateTime.utc_now(),
+          message: "Foreign"
+        })
+
+      {:ok, view, _html} = live(conn, ~p"/dashboard")
+      html = render_click(view, "acknowledge_alert", %{"id" => alert.id})
+      assert html =~ "Alert not found"
+    end
+  end
+
   defp create_device(organization, site, name \\ "Test Device", ip \\ "192.168.1.1") do
     Towerops.Devices.create_device(%{
       name: name,