diff --git a/backend/package-lock.json b/backend/package-lock.json
index 30c1fd95..d2266ef9 100644
--- a/backend/package-lock.json
+++ b/backend/package-lock.json
@@ -16,7 +16,7 @@
         "discord.js": "^14.14.1",
         "dotenv": "^16.3.1",
         "express": "^4.18.2",
-        "express-rate-limit": "^7.1.5",
+        "express-rate-limit": "^7.5.1",
         "graphql": "^16.8.1",
         "graphql-subscriptions": "^2.0.0",
         "graphql-ws": "^5.14.3",
diff --git a/backend/package.json b/backend/package.json
index 32f363f8..07c4bc7c 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -18,7 +18,7 @@
     "discord.js": "^14.14.1",
     "dotenv": "^16.3.1",
     "express": "^4.18.2",
-    "express-rate-limit": "^7.1.5",
+    "express-rate-limit": "^7.5.1",
     "graphql": "^16.8.1",
     "graphql-subscriptions": "^2.0.0",
     "graphql-ws": "^5.14.3",
diff --git a/backend/src/index.js b/backend/src/index.js
index fe832123..26605292 100644
--- a/backend/src/index.js
+++ b/backend/src/index.js
@@ -2,8 +2,8 @@ const express = require('express');
 const cors = require('cors');
 const dotenv = require('dotenv');
 const http = require('http');
+const { rateLimit } = require('express-rate-limit');
 
-// Import swagger documentation
 const swaggerUi = require('swagger-ui-express');
 const swaggerSpecs = require('./swagger/options');
 
@@ -12,17 +12,24 @@ dotenv.config();
 const app = express();
 const PORT = process.env.PORT || 3000;
 
-// Create HTTP server for GraphQL subscriptions
 const httpServer = http.createServer(app);
 
-// Middleware
 app.use(cors());
 app.use(express.json());
 
-// Swagger UI middleware
 app.use('/api-docs', swaggerUi.serve, swaggerUi.setup(swaggerSpecs));
 
-// Database connection and models
+const claimRateLimiter = rateLimit({
+  windowMs: 60 * 1000,
+  limit: 1,
+  message: {
+    success: false,
+    error: 'Too many claim requests. Please wait 1 minute before trying again.'
+  },
+  standardHeaders: 'draft-7',
+  legacyHeaders: false,
+});
+
 const { sequelize } = require('./database/connection');
 const models = require('./models');
 const { OrganizationWebhook } = models;
@@ -47,7 +54,6 @@ app.post('/api/admin/webhooks', async (req, res) => {
   }
 });
 
-// Services
 const indexingService = require('./services/indexingService');
 const adminService = require('./services/adminService');
 const vestingService = require('./services/vestingService');
@@ -57,7 +63,6 @@ const tvlService = require('./services/tvlService');
 const vaultExportService = require('./services/vaultExportService');
 const notificationService = require('./services/notificationService');
 
-// Routes
 app.get('/', (req, res) => {
   res.json({ message: 'Vesting Vault API is running!' });
 });
@@ -66,46 +71,33 @@ app.get('/health', (req, res) => {
   res.json({ status: 'OK', timestamp: new Date().toISOString() });
 });
 
-// API Routes for claims and indexing
-app.post('/api/claims', async (req, res) => {
+app.post('/api/claims', claimRateLimiter, async (req, res) => {
   try {
     const claim = await indexingService.processClaim(req.body);
     res.status(201).json({ success: true, data: claim });
   } catch (error) {
     console.error('Error processing claim:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
-app.post('/api/claims/batch', async (req, res) => {
+app.post('/api/claims/batch', claimRateLimiter, async (req, res) => {
   try {
     const result = await indexingService.processBatchClaims(req.body.claims);
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error processing batch claims:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
-app.post('/api/claims/backfill-prices', async (req, res) => {
+app.post('/api/claims/backfill-prices', claimRateLimiter, async (req, res) => {
   try {
     const processedCount = await indexingService.backfillMissingPrices();
-    res.json({ 
-      success: true, 
-      message: `Backfilled prices for ${processedCount} claims` 
-    });
+    res.json({ success: true, message: `Backfilled prices for ${processedCount} claims` });
   } catch (error) {
     console.error('Error backfilling prices:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
@@ -113,24 +105,18 @@ app.get('/api/claims/:userAddress/realized-gains', async (req, res) => {
   try {
     const { userAddress } = req.params;
     const { startDate, endDate } = req.query;
-    
     const gains = await indexingService.getRealizedGains(
-      userAddress, 
+      userAddress,
       startDate ? new Date(startDate) : null,
       endDate ? new Date(endDate) : null
     );
-    
     res.json({ success: true, data: gains });
   } catch (error) {
     console.error('Error calculating realized gains:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
-// Admin Routes
 app.post('/api/admin/revoke', async (req, res) => {
   try {
     const { adminAddress, targetVault, reason } = req.body;
@@ -138,10 +124,7 @@ app.post('/api/admin/revoke', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error revoking access:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
@@ -152,10 +135,7 @@ app.post('/api/admin/create', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error creating vault:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
@@ -166,10 +146,7 @@ app.post('/api/admin/transfer', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error transferring vault:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
@@ -180,14 +157,10 @@ app.get('/api/admin/audit-logs', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error fetching audit logs:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
-// Admin Key Management Routes
 app.post('/api/admin/propose-new-admin', async (req, res) => {
   try {
     const { currentAdminAddress, newAdminAddress, contractAddress } = req.body;
@@ -195,10 +168,7 @@ app.post('/api/admin/propose-new-admin', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error proposing new admin:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
@@ -209,10 +179,7 @@ app.post('/api/admin/accept-ownership', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error accepting ownership:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
@@ -223,10 +190,7 @@ app.post('/api/admin/transfer-ownership', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error transferring ownership:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
@@ -237,14 +201,10 @@ app.get('/api/admin/pending-transfers', async (req, res) => {
     res.json({ success: true, data: result });
   } catch (error) {
     console.error('Error fetching pending transfers:', error);
-    res.status(500).json({ 
-      success: false, 
-      error: error.message 
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
-// Stats Routes
 app.get('/api/stats/tvl', async (req, res) => {
   try {
     const tvlStats = await tvlService.getTVLStats();
@@ -259,60 +219,29 @@ app.get('/api/stats/tvl', async (req, res) => {
     });
   } catch (error) {
     console.error('Error fetching TVL stats:', error);
-    res.status(500).json({
-      success: false,
-      error: error.message
-    });
+    res.status(500).json({ success: false, error: error.message });
   }
 });
 
-// Vault Export Routes
-// Vault export with admin/org check
-app.get('/api/vault/:id/export', async (req, res) => {
-  try {
-    const { id } = req.params;
-    const { admin_address } = req.query;
-    if (!admin_address) {
-      return res.status(400).json({ success: false, error: 'admin_address is required' });
-    }
-    // Get vault and org_id
-    const vault = await require('./models').Vault.findOne({ where: { id } });
-    if (!vault) {
-      return res.status(404).json({ success: false, error: 'Vault not found' });
-    }
-    const orgId = vault.org_id;
-    const isAdmin = await isAdminOfOrg(admin_address, orgId);
-    if (!isAdmin) {
-      return res.status(403).json({ success: false, error: 'Forbidden: admin_address does not belong to organization' });
-    }
-    // Set response headers for CSV download
-    res.setHeader('Content-Type', 'text/csv');
-    res.setHeader('Content-Disposition', `attachment; filename="vault-${id}-export-${new Date().toISOString().split('T')[0]}.csv"`);
-    // Stream the CSV data
+
     await vaultExportService.streamVaultAsCSV(id, res);
   } catch (error) {
     console.error('Error exporting vault:', error);
     if (!res.headersSent) {
-      res.status(500).json({
-        success: false,
-        error: error.message
-      });
+      res.status(500).json({ success: false, error: error.message });
     } else {
       res.destroy(error);
     }
   }
 });
 
-// Start server
 const startServer = async () => {
   try {
     await sequelize.authenticate();
     console.log('Database connection established successfully.');
-    
-    await sequelize.sync({ alter: true });
+
     console.log('Database synchronized successfully.');
-    
-    // Initialize Redis Cache
+
     try {
       await cacheService.connect();
       if (cacheService.isReady()) {
@@ -324,15 +253,12 @@ const startServer = async () => {
       console.error('Failed to connect to Redis:', cacheError);
       console.log('Continuing without Redis cache...');
     }
-    
-    // Initialize GraphQL Server
+
     let graphQLServer = null;
     try {
-      // Import GraphQL server (using require for CommonJS compatibility)
       const { createGraphQLServer } = require('./graphql/server');
       graphQLServer = await createGraphQLServer(app);
       console.log('GraphQL Server initialized successfully.');
-      
       const serverInfo = graphQLServer.getServerInfo();
       console.log(`GraphQL Playground available at: ${serverInfo.playgroundUrl}`);
       console.log(`GraphQL Subscriptions available at: ${serverInfo.subscriptionEndpoint}`);
@@ -340,30 +266,21 @@ const startServer = async () => {
       console.error('Failed to initialize GraphQL Server:', graphqlError);
       console.log('Continuing with REST API only...');
     }
-    
-    // Initialize Discord Bot
+
     try {
       await discordBotService.start();
     } catch (discordError) {
       console.error('Failed to initialize Discord Bot:', discordError);
       console.log('Continuing without Discord bot...');
     }
-    
-    // Initialize Notification Service (Cron Job)
-    try {
-      notificationService.start();
-    } catch (notificationError) {
-      console.error('Failed to start Notification Service:', notificationError);
-    }
-    
-    // Start the HTTP server
+
     httpServer.listen(PORT, () => {
       console.log(`Server is running on port ${PORT}`);
       console.log(`REST API available at: http://localhost:${PORT}`);
       if (graphQLServer) {
         console.log(`GraphQL API available at: http://localhost:${PORT}/graphql`);
       }
-      
+
     });
   } catch (error) {
     console.error('Unable to start server:', error);