diff --git a/src/config/database.js b/src/config/database.js
index 5668f26..639ab0f 100644
--- a/src/config/database.js
+++ b/src/config/database.js
@@ -259,7 +259,8 @@ const ready = new Promise(resolve => { _readyResolve = resolve; });
     'ALTER TABLE users ADD COLUMN is_organizer INTEGER DEFAULT 0',
     'ALTER TABLE hunts ADD COLUMN start_date DATETIME',
     'ALTER TABLE hunts ADD COLUMN hidden_until_start INTEGER DEFAULT 0',
-    'ALTER TABLE users ADD COLUMN display_name TEXT'
+    'ALTER TABLE users ADD COLUMN display_name TEXT',
+    'ALTER TABLE complaint_reports ADD COLUMN reporter_ip TEXT'
   ];
   for (const m of migrations) {
     try { _db.run(m); } catch (e) { /* column already exists */ }
diff --git a/src/models/index.js b/src/models/index.js
index f728117..0088b0f 100644
--- a/src/models/index.js
+++ b/src/models/index.js
@@ -536,12 +536,31 @@ const OrganizerApplications = {
 
 // ─── Complaint Reports ───────────────────────────────────
 const ComplaintReports = {
-  submit({ huntId, packageId, reportedByUserId, reporterName, reporterContact, message }) {
+  submit({ huntId, packageId, reportedByUserId, reporterName, reporterContact, message, reporterIp }) {
     return db.prepare(`
       INSERT INTO complaint_reports
-      (hunt_id, package_id, reported_by_user_id, reporter_name, reporter_contact, message)
-      VALUES (?, ?, ?, ?, ?, ?)
-    `).run(huntId, packageId, reportedByUserId || null, reporterName || null, reporterContact || null, message).lastInsertRowid;
+      (hunt_id, package_id, reported_by_user_id, reporter_name, reporter_contact, message, reporter_ip)
+      VALUES (?, ?, ?, ?, ?, ?, ?)
+    `).run(huntId, packageId, reportedByUserId || null, reporterName || null, reporterContact || null, message, reporterIp || null).lastInsertRowid;
+  },
+
+  hasOpenFromIp(packageId, ip) {
+    if (!ip) return false;
+    const row = db.prepare(`
+      SELECT id FROM complaint_reports
+      WHERE package_id = ? AND reporter_ip = ? AND status = 'open'
+      LIMIT 1
+    `).get(packageId, ip);
+    return !!row;
+  },
+
+  countRecentFromIp(ip, windowMinutes = 60) {
+    if (!ip) return 0;
+    const row = db.prepare(`
+      SELECT COUNT(*) as cnt FROM complaint_reports
+      WHERE reporter_ip = ? AND created_at > datetime('now', ? || ' minutes')
+    `).get(ip, `-${windowMinutes}`);
+    return row ? row.cnt : 0;
   },
 
   getOpenByHunt(huntId) {
diff --git a/src/routes/hunts.js b/src/routes/hunts.js
index 7ad8e11..5d7e524 100644
--- a/src/routes/hunts.js
+++ b/src/routes/hunts.js
@@ -111,6 +111,19 @@ router.post('/hunt/:shortName/:cardNumber/report', (req, res) => {
   const reporterName = (req.body.reporter_name || '').trim();
   const reporterContact = (req.body.reporter_contact || '').trim();
   const message = (req.body.message || '').trim();
+  const reporterIp = req.ip || null;
+
+  // Rate limit: max 5 reports per IP per hour
+  if (reporterIp && ComplaintReports.countRecentFromIp(reporterIp, 60) >= 5) {
+    req.session.flash = { type: 'danger', message: 'Too many reports submitted recently. Please wait a while before trying again.' };
+    return res.redirect(`/hunt/${pkg.hunt_short_name}/${pkg.card_number}/report`);
+  }
+
+  // Duplicate suppression: same IP already has an open complaint for this package
+  if (reporterIp && ComplaintReports.hasOpenFromIp(pkg.id, reporterIp)) {
+    req.session.flash = { type: 'warning', message: 'You\'ve already submitted a report for this item and it\'s still being reviewed.' };
+    return res.redirect(`/hunt/${pkg.hunt_short_name}/${pkg.card_number}`);
+  }
 
   if (!message || message.length < 10) {
     req.session.flash = { type: 'danger', message: 'Please include a short description (at least 10 characters).' };
@@ -127,6 +140,7 @@ router.post('/hunt/:shortName/:cardNumber/report', (req, res) => {
     reportedByUserId: req.session && req.session.userId ? req.session.userId : null,
     reporterName: reporterName || null,
     reporterContact: reporterContact || null,
+    reporterIp,
     message
   });