diff --git a/src/lib/click-query-params.ts b/src/lib/click-query-params.ts
index 56d337f..3ba9657 100644
--- a/src/lib/click-query-params.ts
+++ b/src/lib/click-query-params.ts
@@ -1,4 +1,4 @@
-const CLICK_QUERY_PARAM_ALLOWLIST = ['u'] as const;
+const CLICK_QUERY_PARAM_ALLOWLIST = ['userId', 'path'] as const;
 
 type ClickQueryParamKey = typeof CLICK_QUERY_PARAM_ALLOWLIST[number];
 
diff --git a/src/lib/fingerprint.test.ts b/src/lib/fingerprint.test.ts
index 846d4be..5d3e355 100644
--- a/src/lib/fingerprint.test.ts
+++ b/src/lib/fingerprint.test.ts
@@ -403,7 +403,7 @@ describe('recordInstallEvent', () => {
           click_id: 'click-merge',
           link_id: 'link-merge',
           clicked_at: clickTime,
-          click_query_params: { u: 'abc' },
+          click_query_params: { userId: 'study3144', path: '/invite', u: 'abc' },
           attribution_window_hours: 24,
           ip_address: '24.5.10.250',
           user_agent:
@@ -440,12 +440,17 @@ describe('recordInstallEvent', () => {
     expect(result.match).not.toBeNull();
     expect(result.deepLinkData.deepLinkParameters).toEqual({
       pid: 'recommend_user',
-      u: 'abc',
+      userId: 'study3144',
+      path: '/invite',
     });
     expect(result.deepLinkData.customParameters).toEqual({
       pid: 'recommend_user',
-      u: 'abc',
+      userId: 'study3144',
+      path: '/invite',
+    });
+    expect(result.deepLinkData.clickQueryParameters).toEqual({
+      userId: 'study3144',
+      path: '/invite',
     });
-    expect(result.deepLinkData.clickQueryParameters).toEqual({ u: 'abc' });
   });
 });
diff --git a/src/lib/fingerprint.ts b/src/lib/fingerprint.ts
index c0da968..4254053 100644
--- a/src/lib/fingerprint.ts
+++ b/src/lib/fingerprint.ts
@@ -1,5 +1,6 @@
 import crypto from 'crypto';
 import { db } from './database.js';
+import { extractAllowedClickQueryParams } from './click-query-params.js';
 
 /**
  * Device fingerprint data structure
@@ -263,13 +264,14 @@ function normalizeClickQueryParams(value: unknown): Record<string, string> {
 
   if (typeof source !== 'object' || Array.isArray(source)) return {};
 
-  const result: Record<string, string> = {};
+  const queryLike: Record<string, string | undefined> = {};
   for (const [k, v] of Object.entries(source as Record<string, unknown>)) {
-    if (typeof v === 'string') {
-      result[k] = v;
+    if (typeof v === 'string' && v.length > 0) {
+      queryLike[k] = v;
     }
   }
-  return result;
+
+  return extractAllowedClickQueryParams(queryLike);
 }
 
 function scoreFingerprintMatch(