diff --git a/app/controllers/admin/categories_controller.rb b/app/controllers/admin/categories_controller.rb
index df6fd128c..8d52212bb 100644
--- a/app/controllers/admin/categories_controller.rb
+++ b/app/controllers/admin/categories_controller.rb
@@ -52,7 +52,7 @@ def update
     start = Time.now
     begin
       category = LinkedData::Client::Models::Category.find_by_acronym(params[:id], include: ATTRIBUTE_TO_INCLUDE ).first
-      add_ontologies_to_object(category_params[:ontologies],category) if (category_params[:ontologies].size > 0 && category_params[:ontologies].first != '')
+      add_ontologies_to_object(category_params[:ontologies],category) if (category_params[:ontologies].present? && category_params[:ontologies].size > 0 && category_params[:ontologies].first != '')
       delete_ontologies_from_object(category_params[:ontologies],category.ontologies,category) 
       category.update_from_params(category_params)
       category_update = category.update
diff --git a/app/controllers/admin/groups_controller.rb b/app/controllers/admin/groups_controller.rb
index 17bc12511..3df27d2e0 100644
--- a/app/controllers/admin/groups_controller.rb
+++ b/app/controllers/admin/groups_controller.rb
@@ -52,7 +52,7 @@ def update
     start = Time.now
     begin
       group = LinkedData::Client::Models::Group.find_by_acronym(params[:id]).first
-      add_ontologies_to_object(group_params[:ontologies],group) if (group_params[:ontologies].size > 0 && group_params[:ontologies].first != '')
+      add_ontologies_to_object(group_params[:ontologies],group) if (group_params[:ontologies].present? && group_params[:ontologies].size > 0 && group_params[:ontologies].first != '')
       delete_ontologies_from_object(group_params[:ontologies],group.ontologies,group)
       group.update_from_params(group_params)
       group_updated = group.update
diff --git a/app/controllers/concerns/submission_updater.rb b/app/controllers/concerns/submission_updater.rb
index d283b82c0..85fe4306d 100644
--- a/app/controllers/concerns/submission_updater.rb
+++ b/app/controllers/concerns/submission_updater.rb
@@ -48,6 +48,7 @@ def add_ontologies_to_object(ontologies,object)
   end
 
   def delete_ontologies_from_object(new_ontologies,old_ontologies,object)
+    new_ontologies = [] if new_ontologies.nil?
     ontologies = old_ontologies - new_ontologies
     ontologies.each do |ont|
       ontology = LinkedData::Client::Models::Ontology.find(ont)