diff --git a/src/client/spark/Modules/Trading/OrderBook/OrderBookColumns.cs b/src/client/spark/Modules/Trading/OrderBook/OrderBookColumns.cs
index 1ba081d1b..c4a4b82ed 100644
--- a/src/client/spark/Modules/Trading/OrderBook/OrderBookColumns.cs
+++ b/src/client/spark/Modules/Trading/OrderBook/OrderBookColumns.cs
@@ -63,6 +63,7 @@ namespace mbts.spark {
          readonly List<ICVOrderBookColumn> _active_comparers = new List<ICVOrderBookColumn>();
 
          public OrderBookColumnCollection(IBus bus, OrdersModel model, IObservable<(IEnumerable<SecurityImmutable> added, IEnumerable<SecurityImmutable> removed)> order_securities) {
+            // security
             Add(security_column = new SecurityColumn(
                DiscreteValuesFilterVM.Create<OrderRecordTuple, SecurityImmutable, SecurityCriteria>(
                   order_securities,