diff --git a/lib/jsonapi/resource_set.rb b/lib/jsonapi/resource_set.rb
index ef3c285ee..b1fb136bf 100644
--- a/lib/jsonapi/resource_set.rb
+++ b/lib/jsonapi/resource_set.rb
@@ -47,7 +47,6 @@ def populate!(serializer, context, find_options)
             )
           )
         else
-          missed_resource_ids[resource_klass] ||= {}
           missed_resource_ids[resource_klass] = @resource_klasses[resource_klass].keys
         end
       end