diff --git a/process/Contact_lib/process.js b/process/Contact_lib/process.js
index e62bcfe34e30642c47b40f43c61f103a1ee99878..09c53387243396a1d82be38c42de96ba4fadbff3 100644
--- a/process/Contact_lib/process.js
+++ b/process/Contact_lib/process.js
@@ -744,7 +744,7 @@ ContactUtils.getCommFilter = function(pOperator, pRawvalue, pFilterOperatorName,
             resultSqlCond = resultSqlCond + " '%" + pRawvalue + "')";
             break;
         case "ISNULL":
-            resultSqlCond = "CONTACTID not in " + commpart + ")";
+            resultSqlCond = "CONTACTID not in (" + commpart + ")";
             break;
         case "ISNOTNULL":
             resultSqlCond = resultSqlCond + ")";