diff --git a/lib/i18n/tasks/scanners/base_scanner.rb b/lib/i18n/tasks/scanners/base_scanner.rb
index 67995c16..024b2421 100644
--- a/lib/i18n/tasks/scanners/base_scanner.rb
+++ b/lib/i18n/tasks/scanners/base_scanner.rb
@@ -120,7 +120,7 @@ def strip_literal(literal)
     VALID_KEY_RE = /^(#{VALID_KEY_CHARS}|[\#{@}])+$/
 
     def valid_key?(key, strict = false)
-      return false if @key_filter && @key_filter_pattern !~ key
+      return false if key_filter && @key_filter_pattern !~ key
       if strict
         key =~ VALID_KEY_RE_STRICT && !key.end_with?('.')
       else