diff --git a/CHANGELOG.md b/CHANGELOG.md
index fdc7d3a3e..b4e6b62ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@
 * [#2918](https://github.com/ruby-grape/grape/pull/2918): Skip the dry-types round trip when a value already is the declared type - [@ericproulx](https://github.com/ericproulx).
 * [#2917](https://github.com/ruby-grape/grape/pull/2917): Read path captures out of the router's union match instead of re-running the route's pattern - [@ericproulx](https://github.com/ericproulx).
 * [#2921](https://github.com/ruby-grape/grape/pull/2921): Pin the router's request-time isolation regressions through requests instead of its instance variables - [@ericproulx](https://github.com/ericproulx).
+* [#2925](https://github.com/ruby-grape/grape/pull/2925): Skip the qualifying-params lookup for params scopes other than `given` - [@ericproulx](https://github.com/ericproulx).
 * Your contribution here.
 
 ### 4.0.0 (2026-09-07)
diff --git a/lib/grape/validations/params_scope.rb b/lib/grape/validations/params_scope.rb
index be26ab992..099ede647 100644
--- a/lib/grape/validations/params_scope.rb
+++ b/lib/grape/validations/params_scope.rb
@@ -5,7 +5,14 @@ module Validations
     class ParamsScope
       attr_reader :parent, :type, :nearest_array_ancestor, :array_depth, :full_path
 
+      # The elements a +given+ scope narrowed its Array params down to during
+      # this request (see #meets_dependency?). Only a scope with a dependency
+      # ever stores any, so every other scope answers without the fiber-storage
+      # and tracker lookups -- which #params pays on each nested resolution,
+      # twice per validator, on every request.
       def qualifying_params
+        return unless @dependent_on
+
         ParamScopeTracker.current&.qualifying_params(self)
       end