diff --git a/buffet/device_registration_info.cc b/buffet/device_registration_info.cc
index b44498d..a4e30e1 100644
--- a/buffet/device_registration_info.cc
+++ b/buffet/device_registration_info.cc
@@ -402,7 +402,8 @@
 std::string DeviceRegistrationInfo::RegisterDevice(
     const std::map<std::string, std::string>& params,
     chromeos::ErrorPtr* error) {
-  if (!GetParamValue(params, "ticket_id", &ticket_id_, error) ||
+  std::string ticket_id;
+  if (!GetParamValue(params, "ticket_id", &ticket_id, error) ||
       !GetParamValue(params, storage_keys::kClientId, &client_id_, error) ||
       !GetParamValue(params, storage_keys::kClientSecret, &client_secret_,
                      error) ||
@@ -425,11 +426,11 @@
     return std::string();
 
   base::DictionaryValue req_json;
-  req_json.SetString("id", ticket_id_);
+  req_json.SetString("id", ticket_id);
   req_json.SetString("oauthClientId", client_id_);
   req_json.Set("deviceDraft", device_draft.release());
 
-  auto url = GetServiceURL("registrationTickets/" + ticket_id_,
+  auto url = GetServiceURL("registrationTickets/" + ticket_id,
                            {{"key", api_key_}});
   std::unique_ptr<chromeos::http::Response> response =
       chromeos::http::PatchJsonAndBlock(url, &req_json, {}, transport_, error);
@@ -442,7 +443,7 @@
     return std::string();
   }
 
-  url = GetServiceURL("registrationTickets/" + ticket_id_ +
+  url = GetServiceURL("registrationTickets/" + ticket_id +
                       "/finalize?key=" + api_key_);
   response = chromeos::http::SendRequestWithNoDataAndBlock(
       chromeos::http::request_type::kPost, url, {}, transport_, error);
diff --git a/buffet/device_registration_info.h b/buffet/device_registration_info.h
index 96979dc..046ba7f 100644
--- a/buffet/device_registration_info.h
+++ b/buffet/device_registration_info.h
@@ -211,7 +211,6 @@
   // Transient data
   std::string access_token_;
   base::Time access_token_expiration_;
-  std::string ticket_id_;
 
   // HTTP transport used for communications.
   std::shared_ptr<chromeos::http::Transport> transport_;
diff --git a/buffet/device_registration_info_unittest.cc b/buffet/device_registration_info_unittest.cc
index 676048f..2b274e0 100644
--- a/buffet/device_registration_info_unittest.cc
+++ b/buffet/device_registration_info_unittest.cc
@@ -161,10 +161,6 @@
 // DeviceRegistrationInfo.
 class DeviceRegistrationInfo::TestHelper {
  public:
-  static void SetTestTicketId(DeviceRegistrationInfo* info) {
-    info->ticket_id_ = test_data::kClaimTicketId;
-  }
-
   static bool Save(DeviceRegistrationInfo* info) {
     return info->Save();
   }
@@ -415,7 +411,6 @@
                          chromeos::http::request_type::kPost,
                          base::Bind(OAuth2Handler));
   storage_->reset_save_count();
-  DeviceRegistrationInfo::TestHelper::SetTestTicketId(dev_reg_.get());
 
   std::map<std::string, std::string> params;
   params["ticket_id"] = test_data::kClaimTicketId;