diff --git a/omaha_request_action.cc b/omaha_request_action.cc
index de02b5e..6adacc3 100644
--- a/omaha_request_action.cc
+++ b/omaha_request_action.cc
@@ -149,6 +149,7 @@
                   OmahaRequestParams* params,
                   bool ping_only,
                   bool include_ping,
+                  bool skip_updatecheck,
                   int ping_active_days,
                   int ping_roll_call_days,
                   PrefsInterface* prefs) {
@@ -157,17 +158,20 @@
     if (include_ping)
         app_body = GetPingXml(ping_active_days, ping_roll_call_days);
     if (!ping_only) {
-      app_body += "        <updatecheck";
-      if (!params->target_version_prefix().empty()) {
-        app_body += base::StringPrintf(
-            " targetversionprefix=\"%s\"",
-            XmlEncodeWithDefault(params->target_version_prefix(), "").c_str());
-        // Rollback requires target_version_prefix set.
-        if (params->rollback_allowed()) {
-          app_body += " rollback_allowed=\"true\"";
+      if (!skip_updatecheck) {
+        app_body += "        <updatecheck";
+        if (!params->target_version_prefix().empty()) {
+          app_body += base::StringPrintf(
+              " targetversionprefix=\"%s\"",
+              XmlEncodeWithDefault(params->target_version_prefix(), "")
+                  .c_str());
+          // Rollback requires target_version_prefix set.
+          if (params->rollback_allowed()) {
+            app_body += " rollback_allowed=\"true\"";
+          }
         }
+        app_body += "></updatecheck>\n";
       }
-      app_body += "></updatecheck>\n";
 
       // If this is the first update check after a reboot following a previous
       // update, generate an event containing the previous version number. If
@@ -266,12 +270,18 @@
                  const OmahaAppData& app_data,
                  bool ping_only,
                  bool include_ping,
+                 bool skip_updatecheck,
                  int ping_active_days,
                  int ping_roll_call_days,
                  int install_date_in_days,
                  SystemState* system_state) {
-  string app_body = GetAppBody(event, params, ping_only, include_ping,
-                               ping_active_days, ping_roll_call_days,
+  string app_body = GetAppBody(event,
+                               params,
+                               ping_only,
+                               include_ping,
+                               skip_updatecheck,
+                               ping_active_days,
+                               ping_roll_call_days,
                                system_state->prefs());
   string app_versions;
 
@@ -402,12 +412,13 @@
       .id = params->GetAppId(),
       .version = params->app_version(),
       .product_components = params->product_components()};
-  // TODO(xiaochu): send update check flag only when operation is update.
+  // Skips updatecheck for platform app in case of an install operation.
   string app_xml = GetAppXml(event,
                              params,
                              product_app,
                              ping_only,
                              include_ping,
+                             params->is_install(), /* skip_updatecheck */
                              ping_active_days,
                              ping_roll_call_days,
                              install_date_in_days,
@@ -420,6 +431,7 @@
                          system_app,
                          ping_only,
                          include_ping,
+                         false, /* skip_updatecheck */
                          ping_active_days,
                          ping_roll_call_days,
                          install_date_in_days,
@@ -435,6 +447,7 @@
                          dlc_app,
                          ping_only,
                          include_ping,
+                         false, /* skip_updatecheck */
                          ping_active_days,
                          ping_roll_call_days,
                          install_date_in_days,
@@ -892,7 +905,8 @@
 bool ParsePackage(OmahaParserData::App* app,
                   OmahaResponse* output_object,
                   ScopedActionCompleter* completer) {
-  if (app->updatecheck_status == kValNoUpdate) {
+  if (app->updatecheck_status.empty() ||
+      app->updatecheck_status == kValNoUpdate) {
     if (!app->packages.empty()) {
       LOG(ERROR) << "No update in this <app> but <package> is not empty.";
       completer->set_code(ErrorCode::kOmahaResponseInvalid);
@@ -1085,23 +1099,29 @@
                                      OmahaResponse* output_object,
                                      ScopedActionCompleter* completer) {
   output_object->update_exists = false;
-  for (size_t i = 0; i < parser_data->apps.size(); i++) {
-    const string& status = parser_data->apps[i].updatecheck_status;
+  for (const auto& app : parser_data->apps) {
+    const string& status = app.updatecheck_status;
     if (status == kValNoUpdate) {
       // Don't update if any app has status="noupdate".
-      LOG(INFO) << "No update for <app> " << i;
+      LOG(INFO) << "No update for <app> " << app.id;
       output_object->update_exists = false;
       break;
     } else if (status == "ok") {
-      if (parser_data->apps[i].action_postinstall_attrs[kAttrNoUpdate] ==
-          "true") {
+      auto const& attr_no_update =
+          app.action_postinstall_attrs.find(kAttrNoUpdate);
+      if (attr_no_update != app.action_postinstall_attrs.end() &&
+          attr_no_update->second == "true") {
         // noupdate="true" in postinstall attributes means it's an update to
         // self, only update if there's at least one app really have update.
-        LOG(INFO) << "Update to self for <app> " << i;
+        LOG(INFO) << "Update to self for <app> " << app.id;
       } else {
-        LOG(INFO) << "Update for <app> " << i;
+        LOG(INFO) << "Update for <app> " << app.id;
         output_object->update_exists = true;
       }
+    } else if (status.empty() && params_->is_install() &&
+               params_->GetAppId() == app.id) {
+      // Skips the platform app for install operation.
+      LOG(INFO) << "No payload (and ignore) for <app> " << app.id;
     } else {
       LOG(ERROR) << "Unknown Omaha response status: " << status;
       completer->set_code(ErrorCode::kOmahaResponseInvalid);
@@ -1129,11 +1149,20 @@
       // this is the system app (this check is intentionally skipped if there is
       // no system_app_id set)
       output_object->system_version = app.manifest_version;
+    } else if (params_->is_install() &&
+               app.manifest_version != params_->app_version()) {
+      LOG(WARNING) << "An app has a different version (" << app.manifest_version
+                   << ") that is different than platform app version ("
+                   << params_->app_version() << ")";
     }
     if (!app.action_postinstall_attrs.empty() && attrs.empty()) {
       attrs = app.action_postinstall_attrs;
     }
   }
+  if (params_->is_install()) {
+    LOG(INFO) << "Use request version for Install operation.";
+    output_object->version = params_->app_version();
+  }
   if (output_object->version.empty()) {
     LOG(ERROR) << "Omaha Response does not have version in manifest!";
     completer->set_code(ErrorCode::kOmahaResponseInvalid);
diff --git a/omaha_request_action_unittest.cc b/omaha_request_action_unittest.cc
index 759eeeb..06d937d 100644
--- a/omaha_request_action_unittest.cc
+++ b/omaha_request_action_unittest.cc
@@ -78,8 +78,10 @@
               "Don't change the value of kRollforward infinity unless its "
               "size has been changed in firmware.");
 
+const char kCurrentVersion[] = "0.1.0.0";
 const char kTestAppId[] = "test-app-id";
 const char kTestAppId2[] = "test-app2-id";
+const char kTestAppIdSkipUpdatecheck[] = "test-app-id-skip-updatecheck";
 
 // This is a helper struct to allow unit tests build an update response with the
 // values they care about.
@@ -180,6 +182,9 @@
            (multi_app_no_update
                 ? "<app><updatecheck status=\"noupdate\"/></app>"
                 : "") +
+           (multi_app_skip_updatecheck
+                ? "<app appid=\"" + app_id_skip_updatecheck + "\"></app>"
+                : "") +
            "</response>";
   }
 
@@ -190,6 +195,8 @@
 
   string app_id = kTestAppId;
   string app_id2 = kTestAppId2;
+  string app_id_skip_updatecheck = kTestAppIdSkipUpdatecheck;
+  string current_version = kCurrentVersion;
   string version = "1.2.3.4";
   string version2 = "2.3.4.5";
   string more_info_url = "http://more/info";
@@ -224,6 +231,8 @@
   bool multi_app_self_update = false;
   // Whether to include an additional app with status="noupdate".
   bool multi_app_no_update = false;
+  // Whether to include an additional app with no updatecheck tag.
+  bool multi_app_skip_updatecheck = false;
   // Whether to include more than one package in an app.
   bool multi_package = false;
 
@@ -294,7 +303,7 @@
     request_params_.set_os_sp("service_pack");
     request_params_.set_os_board("x86-generic");
     request_params_.set_app_id(kTestAppId);
-    request_params_.set_app_version("0.1.0.0");
+    request_params_.set_app_version(kCurrentVersion);
     request_params_.set_app_lang("en-US");
     request_params_.set_current_channel("unittest");
     request_params_.set_target_channel("unittest");
@@ -307,6 +316,8 @@
     request_params_.set_target_version_prefix("");
     request_params_.set_rollback_allowed(false);
     request_params_.set_is_powerwash_allowed(false);
+    request_params_.set_is_install(false);
+    request_params_.set_dlc_ids({});
 
     fake_system_state_.set_request_params(&request_params_);
     fake_system_state_.set_prefs(&fake_prefs_);
@@ -3091,6 +3102,7 @@
 
 TEST_F(OmahaRequestActionTest, InstallTest) {
   OmahaResponse response;
+  request_params_.set_is_install(true);
   request_params_.set_dlc_ids({"dlc_no_0", "dlc_no_1"});
   brillo::Blob post_data;
   ASSERT_TRUE(TestUpdateCheck(fake_update_response_.GetUpdateResponse(),
@@ -3109,8 +3121,40 @@
   string post_str(post_data.begin(), post_data.end());
   for (const auto& dlc_id : request_params_.dlc_ids()) {
     EXPECT_NE(string::npos,
-              post_str.find("appid=\"test-app-id_" + dlc_id + "\""));
+              post_str.find("appid=\"" + fake_update_response_.app_id + "_" +
+                            dlc_id + "\""));
   }
+  EXPECT_NE(string::npos,
+            post_str.find("appid=\"" + fake_update_response_.app_id + "\""));
+
+  // Count number of updatecheck tag in response.
+  int updatecheck_count = 0;
+  size_t pos = 0;
+  while ((pos = post_str.find("<updatecheck", pos)) != string::npos) {
+    updatecheck_count++;
+    pos++;
+  }
+  EXPECT_EQ(request_params_.dlc_ids().size(), updatecheck_count);
+}
+
+TEST_F(OmahaRequestActionTest, InstallMissingPlatformVersionTest) {
+  fake_update_response_.multi_app_skip_updatecheck = true;
+  fake_update_response_.multi_app_no_update = false;
+  request_params_.set_is_install(true);
+  request_params_.set_dlc_ids({"dlc_no_0", "dlc_no_1"});
+  request_params_.set_app_id(fake_update_response_.app_id_skip_updatecheck);
+  OmahaResponse response;
+  ASSERT_TRUE(TestUpdateCheck(fake_update_response_.GetUpdateResponse(),
+                              -1,
+                              false,  // ping_only
+                              ErrorCode::kSuccess,
+                              metrics::CheckResult::kUpdateAvailable,
+                              metrics::CheckReaction::kUpdating,
+                              metrics::DownloadErrorCode::kUnset,
+                              &response,
+                              nullptr));
+  EXPECT_TRUE(response.update_exists);
+  EXPECT_EQ(fake_update_response_.current_version, response.version);
 }
 
 }  // namespace chromeos_update_engine