diff --git a/omaha_request_action.cc b/omaha_request_action.cc
index edfea53..e994335 100644
--- a/omaha_request_action.cc
+++ b/omaha_request_action.cc
@@ -34,7 +34,8 @@
 static const char* kTagDeadline = "deadline";
 static const char* kTagDisablePayloadBackoff = "DisablePayloadBackoff";
 static const char* kTagDisplayVersion = "DisplayVersion";
-static const char* kTagIsDeltaPayload = "IsDelta";
+// Deprecated: "IsDelta"
+static const char* kTagIsDeltaPayload = "IsDeltaPayload";
 static const char* kTagMaxFailureCountPerUrl = "MaxFailureCountPerUrl";
 static const char* kTagMaxDaysToScatter = "MaxDaysToScatter";
 // Deprecated: "ManifestSignatureRsa"
diff --git a/omaha_request_action_unittest.cc b/omaha_request_action_unittest.cc
index ece38b8..69d5895 100644
--- a/omaha_request_action_unittest.cc
+++ b/omaha_request_action_unittest.cc
@@ -88,6 +88,7 @@
       "ChromeOSVersion=\"" + display_version + "\" "
       "MoreInfo=\"" + more_info_url + "\" Prompt=\"" + prompt + "\" "
       "IsDelta=\"true\" "
+      "IsDeltaPayload=\"true\" "
       "MaxDaysToScatter=\"" + max_days_to_scatter + "\" "
       "sha256=\"" + hash + "\" "
       "needsadmin=\"" + needsadmin + "\" " +
@@ -732,6 +733,7 @@
       "ChromeOSVersion=\"10.2.3.4\" "
       "Prompt=\"false\" "
       "IsDelta=\"true\" "
+      "IsDeltaPayload=\"false\" "
       "sha256=\"lkq34j5345\" "
       "needsadmin=\"true\" "
       "/></actions></manifest></updatecheck></app></response>";
diff --git a/sample_omaha_v3_response.xml b/sample_omaha_v3_response.xml
index cb3bff7..abba523 100644
--- a/sample_omaha_v3_response.xml
+++ b/sample_omaha_v3_response.xml
@@ -11,7 +11,7 @@
         </packages>
         <actions>
           <action event="update" run="chromeos_3095.0.0_x86-zgb_canary-channel_full_mp-v2.bin-df37843370ddf1e3819a2afeaa934faa.signed"/>
-          <action ChromeOSVersion="3095.0.0" ChromeVersion="24.0.1307.0" IsDelta="true" MaxDaysToScatter="14" MetadataSignatureRsa="xXrO/LahHlKk3YmqEf1qE0PN587Sc2IJV+FN7J7x1h49waNQIy/QwYO4LaOySgETe5JZXtkAEzzqakfJwxQ2pVfzj1GkExwjd5LTn1He2GvA73B8fKbS4bfP7dbUFwD5039xCwf1U2gezFViOiOPiVURx/pEsdhv+Cqx/3HbjIuj5au2dooSyDxLC5AnODzAKyYfAcjMuiLON+9SqmctJW+VjzdY9SbJAnkH2qqVjFyBKAXsYT+hOTIJ3MJpg8OSVxMMtGB99PxbOJ52F37d2Y5Fws/AUkNnNEsan/WRJA1kuWoS6rpeR8JQYuVhLiK2u/KpOcvMVRw3Q2VUxtcAGw==" MetadataSize="58315" event="postinstall" sha256="DIAVxoI+8NpsudUawOA5U92VHlaxQBS3ejN4EPM6T2A="/>
+          <action ChromeOSVersion="3095.0.0" ChromeVersion="24.0.1307.0" IsDelta="true" IsDeltaPayload="false" MaxDaysToScatter="14" MetadataSignatureRsa="xXrO/LahHlKk3YmqEf1qE0PN587Sc2IJV+FN7J7x1h49waNQIy/QwYO4LaOySgETe5JZXtkAEzzqakfJwxQ2pVfzj1GkExwjd5LTn1He2GvA73B8fKbS4bfP7dbUFwD5039xCwf1U2gezFViOiOPiVURx/pEsdhv+Cqx/3HbjIuj5au2dooSyDxLC5AnODzAKyYfAcjMuiLON+9SqmctJW+VjzdY9SbJAnkH2qqVjFyBKAXsYT+hOTIJ3MJpg8OSVxMMtGB99PxbOJ52F37d2Y5Fws/AUkNnNEsan/WRJA1kuWoS6rpeR8JQYuVhLiK2u/KpOcvMVRw3Q2VUxtcAGw==" MetadataSize="58315" event="postinstall" sha256="DIAVxoI+8NpsudUawOA5U92VHlaxQBS3ejN4EPM6T2A="/>
         </actions>
       </manifest>
     </updatecheck>