diff --git a/spec/indexers/hyrax/file_set_indexer_spec.rb b/spec/indexers/hyrax/file_set_indexer_spec.rb
index 5a4ec2cc46..08849182d4 100644
--- a/spec/indexers/hyrax/file_set_indexer_spec.rb
+++ b/spec/indexers/hyrax/file_set_indexer_spec.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
-RSpec.describe Hyrax::FileSetIndexer do
+
+# Marked as AF-only, since Valkyrie FileSet indexing is handled by Hyrax::ValkyrieFileSetIndexer.
+RSpec.describe Hyrax::FileSetIndexer, :active_fedora do
   include Hyrax::FactoryHelpers
 
   let(:file_set) do