diff --git a/modules/criteoBidAdapter.js b/modules/criteoBidAdapter.js
index 8bf92c07f00..7ed6c42ac23 100755
--- a/modules/criteoBidAdapter.js
+++ b/modules/criteoBidAdapter.js
@@ -6,7 +6,7 @@ import find from 'core-js/library/fn/array/find';
 import JSEncrypt from 'jsencrypt/bin/jsencrypt';
 import sha256 from 'crypto-js/sha256';
 
-const ADAPTER_VERSION = 15;
+const ADAPTER_VERSION = 16;
 const BIDDER_CODE = 'criteo';
 const CDB_ENDPOINT = '//bidder.criteo.com/cdb';
 const CRITEO_VENDOR_ID = 91;
@@ -98,6 +98,7 @@ export const spec = {
         const bidId = bidRequest.bidId;
         const bid = {
           requestId: bidId,
+          adId: slot.bidId || utils.getUniqueIdentifierStr(),
           cpm: slot.cpm,
           currency: slot.currency,
           netRevenue: true,
diff --git a/test/spec/modules/criteoBidAdapter_spec.js b/test/spec/modules/criteoBidAdapter_spec.js
index 6dbf51932a0..34fa111260b 100755
--- a/test/spec/modules/criteoBidAdapter_spec.js
+++ b/test/spec/modules/criteoBidAdapter_spec.js
@@ -1,5 +1,7 @@
 import { expect } from 'chai';
 import { cryptoVerify, spec, FAST_BID_PUBKEY } from 'modules/criteoBidAdapter';
+import * as bidfactory from 'src/bidfactory';
+import CONSTANTS from 'src/constants.json';
 import * as utils from 'src/utils';
 
 describe('The Criteo bidding adapter', function () {
@@ -241,6 +243,7 @@ describe('The Criteo bidding adapter', function () {
         body: {
           slots: [{
             impid: 'test-requestId',
+            bidId: 'abc123',
             cpm: 1.23,
             creative: 'test-ad',
             width: 728,
@@ -261,6 +264,7 @@ describe('The Criteo bidding adapter', function () {
       const bids = spec.interpretResponse(response, request);
       expect(bids).to.have.lengthOf(1);
       expect(bids[0].requestId).to.equal('test-bidId');
+      expect(bids[0].adId).to.equal('abc123');
       expect(bids[0].cpm).to.equal(1.23);
       expect(bids[0].ad).to.equal('test-ad');
       expect(bids[0].width).to.equal(728);
@@ -297,6 +301,40 @@ describe('The Criteo bidding adapter', function () {
       expect(bids[0].width).to.equal(728);
       expect(bids[0].height).to.equal(90);
     });
+
+    it('should generate unique adIds if none are returned by the endpoint', function () {
+      const response = {
+        body: {
+          slots: [{
+            impid: 'test-requestId',
+            cpm: 1.23,
+            creative: 'test-ad',
+            width: 300,
+            height: 250,
+          }, {
+            impid: 'test-requestId',
+            cpm: 4.56,
+            creative: 'test-ad',
+            width: 728,
+            height: 90,
+          }],
+        },
+      };
+      const request = {
+        bidRequests: [{
+          adUnitCode: 'test-requestId',
+          bidId: 'test-bidId',
+          sizes: [[300, 250], [728, 90]],
+          params: {
+            networkId: 456,
+          }
+        }]
+      };
+      const bids = spec.interpretResponse(response, request);
+      expect(bids).to.have.lengthOf(2);
+      const prebidBids = bids.map(bid => Object.assign(bidfactory.createBid(CONSTANTS.STATUS.GOOD, request.bidRequests[0]), bid));
+      expect(prebidBids[0].adId).to.not.equal(prebidBids[1].adId);
+    });
   });
 
   describe('cryptoVerify', function () {