diff --git a/app/controllers/seminars_controller.rb b/app/controllers/seminars_controller.rb
index 6db4690..7b3e36f 100644
--- a/app/controllers/seminars_controller.rb
+++ b/app/controllers/seminars_controller.rb
@@ -360,6 +360,7 @@ class SeminarsController < ApplicationController
       'sign_up' => sign_up,
       'contribute_action' => contribute_action,
       'time_now' => time_now,
+      'sign_up_overdue' => sign_up_overdue, 
       'contribute_time_range' => SeminarMain.time_range(seminar.contribute_start_date, seminar.contribute_end_date),
       'sign_up_time_range' => SeminarMain.time_range(seminar.signup_start_date, seminar.signup_end_date),
       'seminar_time_range' => SeminarMain.time_range(seminar.seminar_start_date, seminar.seminar_end_date)
diff --git a/app/views/seminars/show_data.html.erb b/app/views/seminars/show_data.html.erb
index cbef6aa..3a2cd30 100644
--- a/app/views/seminars/show_data.html.erb
+++ b/app/views/seminars/show_data.html.erb
@@ -9,7 +9,8 @@
   @sign_up_time_range = data["sign_up_time_range"]
   @seminar_time_range = data["seminar_time_range"]
   @contribute_time_range = data["contribute_time_range"]
-	@contribute_action = data["contribute_action"]
+  @contribute_action = data["contribute_action"]
+  @sign_up_overdue = data["sign_up_overdue"]
 %>
 
 
@@ -49,7 +50,7 @@
       <td class="seminarive-title-value"><%= @contribute_time_range %></td>
     </tr>
     <% end %>
-    <tr>
+    <tr <%= 'class="hidden"'.html_safe if @sign_up_overdue && @contribute_action.blank? %>>
       <th class="seminarive-title-field"><%= t('seminar.signup') %></th>
       <td class="seminarive-title-value"><%= @sign_up %><br /><%= @contribute_action %></td>
     </tr>