diff --git a/docker/lib/dependabot/docker/utils/helpers.rb b/docker/lib/dependabot/docker/utils/helpers.rb
index 6dbaf93733..bd421e5541 100644
--- a/docker/lib/dependabot/docker/utils/helpers.rb
+++ b/docker/lib/dependabot/docker/utils/helpers.rb
@@ -1,11 +1,16 @@
-# typed: true
+# typed: strong
 # frozen_string_literal: true
 
+require "sorbet-runtime"
+
 module Dependabot
   module Docker
     module Utils
       HELM_REGEXP = /values[\-a-zA-Z_0-9]*\.ya?ml$/i
 
+      extend T::Sig
+
+      sig { params(file: Dependabot::DependencyFile).returns(T::Boolean) }
       def self.likely_helm_chart?(file)
         file.name.match?(HELM_REGEXP)
       end