diff --git a/sublist/sublist.go b/sublist/sublist.go
index 2d38950f..190f1cdd 100644
--- a/sublist/sublist.go
+++ b/sublist/sublist.go
@@ -410,6 +410,25 @@ func matchLiteral(literal, subject []byte) bool {
 	return true
 }
 
+func IsValidLiteralSubject(subject []byte) bool {
+	tsa := [16][]byte{}
+	toks := split(subject, tsa[:0])
+
+	for _, t := range toks {
+		if len(t) == 0 {
+			return false
+		}
+		if len(t) > 1 {
+			continue
+		}
+		switch t[0] {
+		case _PWC, _FWC:
+			return false
+		}
+	}
+	return true
+}
+
 // Count return the number of stored items in the HashMap.
 func (s *Sublist) Count() uint32 { return s.count }
 
diff --git a/sublist/sublist_test.go b/sublist/sublist_test.go
index e4b17aad..09109d7f 100644
--- a/sublist/sublist_test.go
+++ b/sublist/sublist_test.go
@@ -173,9 +173,12 @@ func TestRemoveCleanupWildcards(t *testing.T) {
 	verifyNumLevels(s, 0, t)
 }
 
-func TestMalformedSubjects(t *testing.T) {
+func TestInvalidSubjectsInsert(t *testing.T) {
 	s := New()
 
+	// Insert, or subscribtions, can have wildcards, but not empty tokens,
+	// and can not have a FWC that is not terminal
+
 	// beginning empty token
 	if err := s.Insert([]byte(".foo"), '@'); err != ErrInvalidSubject {
 		t.Fatal("Expected invalid subject error")
@@ -199,7 +202,6 @@ func TestMalformedSubjects(t *testing.T) {
 	}
 }
 
-
 func TestCacheBehavior(t *testing.T) {
 	s := New()
 	literal := []byte("a.b.c")
@@ -226,6 +228,17 @@ func checkBool(b, expected bool, t *testing.T) {
 	}
 }
 
+func TestValidLiteralSubjects(t *testing.T) {
+	checkBool(IsValidLiteralSubject([]byte("foo")), true, t)
+	checkBool(IsValidLiteralSubject([]byte(".foo")), false, t)
+	checkBool(IsValidLiteralSubject([]byte("foo.")), false, t)
+	checkBool(IsValidLiteralSubject([]byte("foo..bar")), false, t)
+	checkBool(IsValidLiteralSubject([]byte("foo.bar.*")), false, t)
+	checkBool(IsValidLiteralSubject([]byte("foo.bar.>")), false, t)
+	checkBool(IsValidLiteralSubject([]byte("*")), false, t)
+	checkBool(IsValidLiteralSubject([]byte(">")), false, t)
+}
+
 func TestMatchLiterals(t *testing.T) {
 	checkBool(matchLiteral([]byte("foo"), []byte("foo")), true, t)
 	checkBool(matchLiteral([]byte("foo"), []byte("bar")), false, t)