diff --git a/ChangeLog.txt b/ChangeLog.txt
index e212e3e37..b148d2320 100644
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -1,5 +1,14 @@
 Google Mobile Ads Unity Plugin Change Log
 
+*************
+Version 3.0.3
+*************
+- Restrict simultaneous rewarded video requests on Android.
+
+Built and tested with:
+- Google Play Services 8.4.0
+- Google Mobile Ads iOS SDK 7.7.0
+
 *************
 Version 3.0.2
 *************
diff --git a/GoogleMobileAds.unitypackage b/GoogleMobileAds.unitypackage
index 162c8e120..8306ab0da 100644
Binary files a/GoogleMobileAds.unitypackage and b/GoogleMobileAds.unitypackage differ
diff --git a/source/android-library/app/src/main/java/com/google/unity/ads/RewardBasedVideo.java b/source/android-library/app/src/main/java/com/google/unity/ads/RewardBasedVideo.java
index ab0db91e9..9e409c8a9 100644
--- a/source/android-library/app/src/main/java/com/google/unity/ads/RewardBasedVideo.java
+++ b/source/android-library/app/src/main/java/com/google/unity/ads/RewardBasedVideo.java
@@ -51,10 +51,18 @@ public class RewardBasedVideo {
      */
     private boolean isLoaded;
 
+    /**
+     * Whether or not there is an ad request in progress.
+     */
+    private boolean isLoading;
+
+    private final Object mLock = new Object();
+
     public RewardBasedVideo(Activity activity, UnityRewardBasedVideoAdListener adListener) {
         this.activity = activity;
         this.adListener = adListener;
         this.isLoaded = false;
+        this.isLoading = false;
     }
 
     /**
@@ -68,13 +76,19 @@ public void run() {
                 rewardBasedVideo.setRewardedVideoAdListener(new RewardedVideoAdListener() {
                     @Override
                     public void onRewardedVideoAdLoaded() {
-                        isLoaded = true;
-                        adListener.onAdLoaded();
+                        synchronized (mLock) {
+                            isLoaded = true;
+                            isLoading = false;
+                            adListener.onAdLoaded();
+                        }
                     }
 
                     @Override
                     public void onRewardedVideoAdFailedToLoad(int errorCode) {
-                        adListener.onAdFailedToLoad(PluginUtils.getErrorReason(errorCode));
+                        synchronized (mLock) {
+                            isLoading = false;
+                            adListener.onAdFailedToLoad(PluginUtils.getErrorReason(errorCode));
+                        }
                     }
 
                     @Override
@@ -121,7 +135,16 @@ public void run() {
                 if (extras != null) {
                     extras.putBoolean("_noRefresh", true);
                 }
-                rewardBasedVideo.loadAd(adUnitId, request);
+                synchronized (mLock) {
+                    if (!isLoading) {
+                        isLoading = true;
+                        rewardBasedVideo.loadAd(adUnitId, request);
+                    } else {
+                        Log.w(PluginUtils.LOGTAG, "Cannot make a new rewarded video ad request "
+                                + "until previous request has completed.");
+                    }
+                }
+
             }
         });
     }
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs b/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs
index 60cae7f23..baacd141c 100644
--- a/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs
@@ -20,7 +20,7 @@ namespace GoogleMobileAds.Api
 {
     public class AdRequest
     {
-        public const string Version = "3.0.2";
+        public const string Version = "3.0.3";
         public const string TestDeviceSimulator = "SIMULATOR";
 
         public class Builder