diff --git a/src/gateway/probe.test.ts b/src/gateway/probe.test.ts
index 4a2374e17cb..8af3c943b6a 100644
--- a/src/gateway/probe.test.ts
+++ b/src/gateway/probe.test.ts
@@ -71,6 +71,16 @@ describe("probeGateway", () => {
     expect(gatewayClientState.options?.deviceIdentity).toBeUndefined();
   });
 
+  it("keeps device identity enabled for authenticated loopback probes with empty auth object", async () => {
+    await probeGateway({
+      url: "ws://127.0.0.1:18789",
+      auth: {},
+      timeoutMs: 1_000,
+    });
+
+    expect(gatewayClientState.options?.deviceIdentity).toBeUndefined();
+  });
+
   it("keeps device identity disabled for unauthenticated loopback probes", async () => {
     await probeGateway({
       url: "ws://127.0.0.1:18789",