diff --git a/src/collective/taxonomy/widget_input.pt b/src/collective/taxonomy/widget_input.pt
index 0045dde..8001fd9 100644
--- a/src/collective/taxonomy/widget_input.pt
+++ b/src/collective/taxonomy/widget_input.pt
@@ -150,7 +150,7 @@ function selectionError() {
       <td>
         <select class=""
                 id="from"
-                multiple=""
+                multiple
                 name="from"
                 size="5"
                 style="width: 100%"