diff --git a/app/controllers/exercises_controller.rb b/app/controllers/exercises_controller.rb
index 7d4d2c43..2c478df0 100644
--- a/app/controllers/exercises_controller.rb
+++ b/app/controllers/exercises_controller.rb
@@ -28,8 +28,13 @@ class ExercisesController < ApplicationController
     1
   end
 
-  def java_course_token
-    "702cbd2a-c84c-4b37-923a-692d7d1532d0"
+  experimental_courses = {
+      "java17" => "702cbd2a-c84c-4b37-923a-692d7d1532d0",
+      "java1" => "0ea88ea9-979a-44a3-b0e4-84ba58e5a05e"
+  }
+
+  def experimental_course?(course_token)
+    experimental_courses.has_value?(course_token)
   end
 
   def batch_update
@@ -176,16 +181,24 @@ class ExercisesController < ApplicationController
     count_interventions_today = UserExerciseIntervention.where(user: current_user).where("created_at >= ?", Time.zone.now.beginning_of_day).count
     user_got_intervention_in_exercise = UserExerciseIntervention.where(user: current_user, exercise: @exercise).size >= max_intervention_count_per_exercise
     user_got_enough_interventions = count_interventions_today >= max_intervention_count_per_day or user_got_intervention_in_exercise
-    is_java_course = @course_token and @course_token.eql?(java_course_token)
+    @is_experimental_course = @course_token and experimental_course?(@course_token)
 
     user_intervention_group = UserGroupSeparator.getInterventionGroup(current_user)
+    @rfc_group = UserGroupSeparator.getRequestforCommentGroup(current_user)
 
     case user_intervention_group
       when :no_intervention
       when :break_intervention
-        @show_break_interventions = (not user_solved_exercise and is_java_course and not user_got_enough_interventions) ? "true" : "false"
+        @show_break_interventions = (is_experimental_course and not user_solved_exercise and not user_got_enough_interventions) ? "true" : "false"
       when :rfc_intervention
-        @show_rfc_interventions = (not user_solved_exercise and is_java_course and not user_got_enough_interventions) ? "true" : "false"
+        @show_rfc_interventions = (is_experimental_course and not user_solved_exercise and not user_got_enough_interventions) ? "true" : "false"
+    end
+
+    case rfc_group
+      when :hide_rfc
+        @hide_rfc_button = "true"
+      when :stale_rfc
+      when :show_rfc
     end
 
     @search = Search.new
@@ -396,6 +409,11 @@ class ExercisesController < ApplicationController
           return
         end
 
+        if @is_experimental_course and @rfc_group == :hide_rfc
+          redirect_to_lti_return_path
+          return
+        end
+
         rfc = @submission.own_unsolved_rfc
         if rfc
           # set a message that informs the user that his own RFC should be closed.
diff --git a/app/views/exercises/_editor.html.slim b/app/views/exercises/_editor.html.slim
index e692b748..672ce195 100644
--- a/app/views/exercises/_editor.html.slim
+++ b/app/views/exercises/_editor.html.slim
@@ -3,6 +3,7 @@
 - consumer_id = @current_user.respond_to?(:external_id) ? @current_user.consumer_id : '' #'tests' #(@current_user.uuid.present? ? @current_user.uuid : '')
 - show_break_interventions = @show_break_interventions || "false"
 - show_rfc_interventions = @show_rfc_interventions || "false"
+- hide_rfc_button = @hide_rfc_button || "false"
 #editor.row data-exercise-id=@exercise.id data-message-depleted=t('exercises.editor.depleted') data-message-timeout=t('exercises.editor.timeout',  permitted_execution_time: @exercise.execution_environment.permitted_execution_time) data-errors-url=execution_environment_errors_path(exercise.execution_environment) data-submissions-url=submissions_path data-user-id=@current_user.id data-user-external-id=external_user_external_id data-working-times-url=working_times_exercise_path(@exercise) data-intervention-save-url=intervention_exercise_path(@exercise) data-rfc-interventions=show_rfc_interventions data-break-interventions=show_break_interventions data-course_token=@course_token data-search-save-url=search_exercise_path(@exercise)
   div id="sidebar" class=(@exercise.hide_file_tree ? 'sidebar-col-collapsed' : 'sidebar-col') = render('editor_file_tree', exercise: @exercise, files: @files)
   div id='output_sidebar' class='output-col-collapsed' = render('exercises/editor_output', external_user_id: external_user_id, consumer_id: consumer_id )
@@ -14,7 +15,8 @@
       = render('editor_button', data: {:'data-placement' => 'top', :'data-tooltip' => true}, icon: 'fa fa-stop', id: 'stop', label: t('exercises.editor.stop'), title: t('shared.tooltips.shortcut', shortcut: 'ALT + r'))
       = render('editor_button', data: {:'data-placement' => 'top', :'data-tooltip' => true}, icon: 'fa fa-rocket', id: 'test', label: t('exercises.editor.test'), title: t('shared.tooltips.shortcut', shortcut: 'ALT + t'))
       = render('editor_button', data: {:'data-placement' => 'top', :'data-tooltip' => true}, icon: 'fa fa-trophy', id: 'assess', label: t('exercises.editor.score'), title: t('shared.tooltips.shortcut', shortcut: 'ALT + s'))
-      = render('editor_button', icon: 'fa fa-comment', id: 'requestComments', label: t('exercises.editor.requestComments'), title: t('exercises.editor.requestCommentsTooltip'))
+      - if not hide_rfc_button
+        = render('editor_button', icon: 'fa fa-comment', id: 'requestComments', label: t('exercises.editor.requestComments'), title: t('exercises.editor.requestCommentsTooltip'))
     - @files.each do |file|
       = render('editor_frame', exercise: exercise, file: file)
     #autosave-label
diff --git a/lib/user_group_separator.rb b/lib/user_group_separator.rb
index 5be05ef6..a0a45863 100644
--- a/lib/user_group_separator.rb
+++ b/lib/user_group_separator.rb
@@ -24,4 +24,15 @@ class UserGroupSeparator
     end
   end
 
+  def self.getRequestforCommentGroup(user)
+    lastDigitId = user.id % 10
+    if lastDigitId < 2 # 0,1
+      :hide_rfc
+    elsif lastDigitId < 4 # 2,3
+      :stale_rfc
+    else # 4,5,6,7,8,9
+      :show_rfc
+    end
+  end
+
 end
\ No newline at end of file