diff --git a/server/license.js b/server/license.js
index f81170c..f0ef70c 100644
--- a/server/license.js
+++ b/server/license.js
@@ -162,7 +162,10 @@ export function checkLicense() {
     }
     base = emptyState({
       state: "licensed",
-      licenseId: payload.licenseId || null,
+      // payload.licenseId is a Uint8Array (raw 16-byte UUID); the canonical
+      // string form is licenseUuid. The frontend treats licenseId as a
+      // string (calls .slice on it), so always send the string here.
+      licenseId: payload.licenseUuid || null,
       entitlements: new Set(payload.entitlements || []),
       expiresAt: payload.expiresAt ? new Date(payload.expiresAt * 1000) : null,
       isTrial: !!(payload.flags & 1),