diff --git a/component/outbound/filter.go b/component/outbound/filter.go
index 3a16a6d..94265d7 100644
--- a/component/outbound/filter.go
+++ b/component/outbound/filter.go
@@ -78,7 +78,10 @@ func (s *DialerSet) filterHit(dialer *dialer.Dialer, filters []*config_parser.Fu
 						break
 					}
 				case "":
-					return false, fmt.Errorf(`key of "filter: %v()" cannot be empty`, filter.Name)
+					if dialer.Name() == param.Val {
+						subFilterHit = true
+						break
+					}
 				default:
 					return false, fmt.Errorf(`unsupported filter key "%v" in "filter: %v()"`, param.Key, filter.Name)
 				}
diff --git a/example.dae b/example.dae
index 7079ae6..9674102 100644
--- a/example.dae
+++ b/example.dae
@@ -68,7 +68,7 @@ group {
     group2 {
         # Filter nodes from global node pool defined by subscription and node section above.
         # Pass node names as input of keyword/regex filter.
-        filter: subtag(regex: '^my_', another_sub) && name(keyword: netflix)
+        filter: subtag(regex: '^my_', another_sub) && !name(keyword: 'ExpireAt:')
 
         # Select the node with min average of the last 10 latencies from the group for every connection.
         policy: min_avg10