diff --git a/lib/topic_query.rb b/lib/topic_query.rb
index bea49045b87..28fb8a05620 100644
--- a/lib/topic_query.rb
+++ b/lib/topic_query.rb
@@ -23,7 +23,6 @@ class TopicQuery
 
       {
         max_posts: zero_or_more,
-        exclude_category_ids: array_zero_or_more,
         min_posts: zero_or_more,
       }
     end
diff --git a/spec/requests/list_controller_spec.rb b/spec/requests/list_controller_spec.rb
index 50530d10e84..51ff5e493ca 100644
--- a/spec/requests/list_controller_spec.rb
+++ b/spec/requests/list_controller_spec.rb
@@ -17,9 +17,6 @@ RSpec.describe ListController do
     end
 
     it "does not return a 500 for invalid input" do
-      get "/latest?exclude_category_ids[]=bob"
-      expect(response.status).to eq(400)
-
       get "/latest?min_posts=bob"
       expect(response.status).to eq(400)