diff --git a/omaha_request_action_unittest.cc b/omaha_request_action_unittest.cc
index d8bef5e..a336bdd 100644
--- a/omaha_request_action_unittest.cc
+++ b/omaha_request_action_unittest.cc
@@ -27,6 +27,7 @@
 using std::vector;
 using testing::_;
 using testing::AllOf;
+using testing::DoAll;
 using testing::Ge;
 using testing::Le;
 using testing::NiceMock;
@@ -71,7 +72,6 @@
                           const string& needsadmin,
                           const string& size,
                           const string& deadline,
-                          Time published_on,
                           const string& max_days_to_scatter) {
   return string(
       "<?xml version=\"1.0\" encoding=\"UTF-8\"?><gupdate "
@@ -82,7 +82,6 @@
       "ChromeOSVersion=\"" + display_version + "\" "
       "MoreInfo=\"" + more_info_url + "\" Prompt=\"" + prompt + "\" "
       "IsDelta=\"true\" "
-      "UpdatePublishedOn=\"" + utils::ToString(published_on) + "\" "
       "MaxDaysToScatter=\"" + max_days_to_scatter + "\" "
       "codebase=\"" + codebase + "\" "
       "hash=\"not-applicable\" "
@@ -111,7 +110,6 @@
                             needsadmin,
                             size,
                             deadline,
-                            Time::Now(),
                             "7");
 }
 
@@ -291,6 +289,7 @@
                       &response,
                       NULL));
   EXPECT_TRUE(response.update_exists);
+  EXPECT_TRUE(response.update_exists);
   EXPECT_EQ("1.2.3.4", response.display_version);
   EXPECT_EQ("http://code/base", response.codebase);
   EXPECT_EQ("http://more/info", response.more_info_url);
@@ -369,7 +368,6 @@
                                          "false",  // needs admin
                                          "123",  // size
                                          "",  // deadline
-                                         Time::Now(), // published on
                                          "7"), // max days to scatter
                       -1,
                       false,  // ping_only
@@ -410,7 +408,6 @@
                                          "false",  // needs admin
                                          "123",  // size
                                          "",  // deadline
-                                         Time::Now(), // published on
                                          "7"), // max days to scatter
                       -1,
                       false,  // ping_only
@@ -451,7 +448,6 @@
                                          "false",  // needs admin
                                          "123",  // size
                                          "",  // deadline
-                                         Time::Now(), // published on
                                          "0"), // max days to scatter
                       -1,
                       false,  // ping_only
@@ -493,7 +489,6 @@
                                          "false",  // needs admin
                                          "123",  // size
                                          "",  // deadline
-                                         Time::Now(), // published on
                                          "7"), // max days to scatter
                       -1,
                       false,  // ping_only
@@ -538,7 +533,6 @@
                                          "false",  // needs admin
                                          "123",  // size
                                          "",  // deadline
-                                         Time::Now(), // published on
                                          "7"), // max days to scatter
                       -1,
                       false,  // ping_only
@@ -585,7 +579,6 @@
                                          "false",  // needs admin
                                          "123",  // size
                                          "",  // deadline
-                                         Time::Now(), // published on
                                          "7"), // max days to scatter
                       -1,
                       false,  // ping_only
@@ -1323,4 +1316,93 @@
   EXPECT_FALSE(response.update_exists);
 }
 
+TEST(OmahaRequestActionTest, TestUpdateFirstSeenAtGetsPersistedFirstTime) {
+  OmahaResponse response;
+  OmahaRequestParams params = kDefaultTestParams;
+  params.wall_clock_based_wait_enabled = true;
+  params.waiting_period = TimeDelta().FromDays(1);
+  params.update_check_count_wait_enabled = false;
+
+  string prefs_dir;
+  EXPECT_TRUE(utils::MakeTempDirectory("/tmp/ue_ut_prefs.XXXXXX",
+                                       &prefs_dir));
+  ScopedDirRemover temp_dir_remover(prefs_dir);
+
+  Prefs prefs;
+  LOG_IF(ERROR, !prefs.Init(FilePath(prefs_dir)))
+      << "Failed to initialize preferences.";
+
+  ASSERT_FALSE(TestUpdateCheck(
+                      &prefs,  // prefs
+                      params,
+                      GetUpdateResponse2(OmahaRequestParams::kAppId,
+                                         "1.2.3.4",  // version
+                                         "http://more/info",
+                                         "true",  // prompt
+                                         "http://code/base",  // dl url
+                                         "HASH1234=",  // checksum
+                                         "false",  // needs admin
+                                         "123",  // size
+                                         "",  // deadline
+                                         "7"), // max days to scatter
+                      -1,
+                      false,  // ping_only
+                      kActionCodeOmahaUpdateDeferredPerPolicy,
+                      &response,
+                      NULL));
+
+  int64 timestamp = 0;
+  ASSERT_TRUE(prefs.GetInt64(kPrefsUpdateFirstSeenAt, &timestamp));
+  ASSERT_TRUE(timestamp > 0);
+  EXPECT_FALSE(response.update_exists);
+}
+
+TEST(OmahaRequestActionTest, TestUpdateFirstSeenAtGetsUsedIfAlreadyPresent) {
+  OmahaResponse response;
+  OmahaRequestParams params = kDefaultTestParams;
+  params.wall_clock_based_wait_enabled = true;
+  params.waiting_period = TimeDelta().FromDays(1);
+  params.update_check_count_wait_enabled = false;
+
+  string prefs_dir;
+  EXPECT_TRUE(utils::MakeTempDirectory("/tmp/ue_ut_prefs.XXXXXX",
+                                       &prefs_dir));
+  ScopedDirRemover temp_dir_remover(prefs_dir);
+
+  Prefs prefs;
+  LOG_IF(ERROR, !prefs.Init(FilePath(prefs_dir)))
+      << "Failed to initialize preferences.";
+
+  // Set the timestamp to a very old value such that it exceeds the
+  // waiting period set above.
+  Time t1;
+  Time::FromString("1/1/2012", &t1);
+  ASSERT_TRUE(prefs.SetInt64(kPrefsUpdateFirstSeenAt, t1.ToInternalValue()));
+  ASSERT_TRUE(TestUpdateCheck(
+                      &prefs,  // prefs
+                      params,
+                      GetUpdateResponse2(OmahaRequestParams::kAppId,
+                                         "1.2.3.4",  // version
+                                         "http://more/info",
+                                         "true",  // prompt
+                                         "http://code/base",  // dl url
+                                         "HASH1234=",  // checksum
+                                         "false",  // needs admin
+                                         "123",  // size
+                                         "",  // deadline
+                                         "7"), // max days to scatter
+                      -1,
+                      false,  // ping_only
+                      kActionCodeSuccess,
+                      &response,
+                      NULL));
+
+  EXPECT_TRUE(response.update_exists);
+
+  // Make sure the timestamp t1 is unchanged showing that it was reused.
+  int64 timestamp = 0;
+  ASSERT_TRUE(prefs.GetInt64(kPrefsUpdateFirstSeenAt, &timestamp));
+  ASSERT_TRUE(timestamp == t1.ToInternalValue());
+}
+
 }  // namespace chromeos_update_engine