diff --git a/app/controllers/api/attachments_controller.rb b/app/controllers/api/attachments_controller.rb
index c81aa0f9..2f615878 100644
--- a/app/controllers/api/attachments_controller.rb
+++ b/app/controllers/api/attachments_controller.rb
@@ -8,10 +8,10 @@ module Api
     COOKIE_STORE_LIMIT = 10
 
     def create
-      submitter = Submitter.find_by!(slug: params[:submitter_slug])
+      @submitter = Submitter.find_by!(slug: params[:submitter_slug])
 
-      unless can_upload?(submitter)
-        Rollbar.error("Can't upload: #{submitter.id}") if defined?(Rollbar)
+      unless can_upload?(@submitter)
+        Rollbar.error("Can't upload: #{@submitter.id}") if defined?(Rollbar)
 
         return render json: { error: I18n.t('form_has_been_archived') }, status: :unprocessable_content
       end
@@ -20,23 +20,23 @@ module Api
         image = Vips::Image.new_from_file(params[:file].path)
 
         if ImageUtils.blank?(image)
-          Rollbar.error("Empty signature: #{submitter.id}") if defined?(Rollbar)
+          Rollbar.error("Empty signature: #{@submitter.id}") if defined?(Rollbar)
 
           return render json: { error: "#{params[:type]} is empty" }, status: :unprocessable_content
         end
 
         if ImageUtils.error?(image)
-          Rollbar.error("Error signature: #{submitter.id}") if defined?(Rollbar)
+          Rollbar.error("Error signature: #{@submitter.id}") if defined?(Rollbar)
 
           return render json: { error: "#{params[:type]} error, try to sign on another device" },
                         status: :unprocessable_content
         end
       end
 
-      attachment = Submitters.create_attachment!(submitter, params)
+      attachment = Submitters.create_attachment!(@submitter, params)
 
-      if params[:remember_signature] == 'true' && submitter.email.present?
-        cookies.encrypted[:signature_uuids] = build_new_cookie_signatures_json(submitter, attachment)
+      if params[:remember_signature] == 'true' && @submitter.email.present?
+        cookies.encrypted[:signature_uuids] = build_new_cookie_signatures_json(@submitter, attachment)
       end
 
       render json: attachment.as_json(only: %i[uuid created_at], methods: %i[url filename content_type])
diff --git a/app/controllers/submit_form_invite_controller.rb b/app/controllers/submit_form_invite_controller.rb
index 413e2b9a..ac7f6db0 100644
--- a/app/controllers/submit_form_invite_controller.rb
+++ b/app/controllers/submit_form_invite_controller.rb
@@ -5,12 +5,12 @@ class SubmitFormInviteController < ApplicationController
   skip_authorization_check
 
   def create
-    submitter = Submitter.find_by!(slug: params[:submit_form_slug])
+    @submitter = Submitter.find_by!(slug: params[:submit_form_slug])
 
-    return head :unprocessable_content unless can_invite?(submitter)
+    return head :unprocessable_content unless can_invite?(@submitter)
 
-    invite_submitters = filter_invite_submitters(submitter, 'invite_by_uuid')
-    optional_invite_submitters = filter_invite_submitters(submitter, 'optional_invite_by_uuid')
+    invite_submitters = filter_invite_submitters(@submitter, 'invite_by_uuid')
+    optional_invite_submitters = filter_invite_submitters(@submitter, 'optional_invite_by_uuid')
 
     ApplicationRecord.transaction do
       (invite_submitters + optional_invite_submitters).each do |item|
@@ -21,18 +21,18 @@ class SubmitFormInviteController < ApplicationController
 
         email = Submissions.normalize_email(attrs[:email])
 
-        submitter.submission.submitters.create!(uuid: attrs[:uuid], email:, account_id: submitter.account_id)
+        @submitter.submission.submitters.create!(uuid: attrs[:uuid], email:, account_id: @submitter.account_id)
 
-        SubmissionEvents.create_with_tracking_data(submitter, 'invite_party', request, { uuid: submitter.uuid })
+        SubmissionEvents.create_with_tracking_data(@submitter, 'invite_party', request, { uuid: @submitter.uuid })
       end
 
-      submitter.submission.update!(submitters_order: :preserved)
+      @submitter.submission.update!(submitters_order: :preserved)
     end
 
-    submitter.submission.submitters.reload
+    @submitter.submission.submitters.reload
 
-    if invite_submitters.all? { |s| submitter.submission.submitters.any? { |e| e.uuid == s['uuid'] } }
-      Submitters::SubmitValues.call(submitter, ActionController::Parameters.new(completed: 'true'), request)
+    if invite_submitters.all? { |s| @submitter.submission.submitters.any? { |e| e.uuid == s['uuid'] } }
+      Submitters::SubmitValues.call(@submitter, ActionController::Parameters.new(completed: 'true'), request)
 
       head :ok
     else
diff --git a/app/controllers/submit_form_metadata_controller.rb b/app/controllers/submit_form_metadata_controller.rb
index 49bf8666..dcdeaa20 100644
--- a/app/controllers/submit_form_metadata_controller.rb
+++ b/app/controllers/submit_form_metadata_controller.rb
@@ -5,19 +5,19 @@ class SubmitFormMetadataController < ApplicationController
   skip_authorization_check
 
   def index
-    submitter = Submitter.find_by!(slug: params[:submit_form_slug])
+    @submitter = Submitter.find_by!(slug: params[:submit_form_slug])
 
-    return head :not_found if submitter.declined_at? ||
-                              submitter.completed_at? ||
-                              submitter.submission.archived_at? ||
-                              submitter.submission.expired? ||
-                              submitter.submission.template&.archived_at? ||
-                              submitter.account.archived_at? ||
-                              !Submitters::AuthorizedForForm.call(submitter, current_user, request)
+    return head :not_found if @submitter.declined_at? ||
+                              @submitter.completed_at? ||
+                              @submitter.submission.archived_at? ||
+                              @submitter.submission.expired? ||
+                              @submitter.submission.template&.archived_at? ||
+                              @submitter.account.archived_at? ||
+                              !Submitters::AuthorizedForForm.call(@submitter, current_user, request)
 
-    submission = submitter.submission
+    submission = @submitter.submission
     values = submission.submitters.reduce({}) { |acc, sub| acc.merge(sub.values) }
-    schema = Submissions.filtered_conditions_schema(submission, values:, include_submitter_uuid: submitter.uuid)
+    schema = Submissions.filtered_conditions_schema(submission, values:, include_submitter_uuid: @submitter.uuid)
 
     documents = schema.filter_map do |item|
       submission.schema_documents.find { |a| a.uuid == item['attachment_uuid'] }
diff --git a/app/controllers/submit_form_values_controller.rb b/app/controllers/submit_form_values_controller.rb
index affd37ba..4242db5f 100644
--- a/app/controllers/submit_form_values_controller.rb
+++ b/app/controllers/submit_form_values_controller.rb
@@ -5,17 +5,17 @@ class SubmitFormValuesController < ApplicationController
   skip_authorization_check
 
   def index
-    submitter = Submitter.find_by!(slug: params[:submit_form_slug])
+    @submitter = Submitter.find_by!(slug: params[:submit_form_slug])
 
-    return render json: {} if submitter.completed_at? ||
-                              submitter.declined_at? ||
-                              submitter.submission.template&.archived_at? ||
-                              submitter.submission.archived_at? ||
-                              submitter.submission.expired? ||
-                              !Submitters::AuthorizedForForm.call(submitter, current_user, request)
+    return render json: {} if @submitter.completed_at? ||
+                              @submitter.declined_at? ||
+                              @submitter.submission.template&.archived_at? ||
+                              @submitter.submission.archived_at? ||
+                              @submitter.submission.expired? ||
+                              !Submitters::AuthorizedForForm.call(@submitter, current_user, request)
 
-    value = submitter.values[params['field_uuid']]
-    attachment = submitter.attachments.where(created_at: params[:after]..).find_by(uuid: value) if value.present?
+    value = @submitter.values[params['field_uuid']]
+    attachment = @submitter.attachments.where(created_at: params[:after]..).find_by(uuid: value) if value.present?
 
     render json: {
       value:,