Thanks for the reply Hans.

However my question is regarding 3 separate columns. Each column has checkboxes with header checkbox as rowchecker. Below is a small snippet from the code. When I click checkbox header "LOACB", all rows under it gets selected. But, when I click on checkbox header "InvByRM", all checkboxes under column named "LOACB" gets selected which is incorrect.

<ISWebGrid:WebGrid ID="WebGrid1" runat="server" ViewStateStorage="Client" StateRestorationLevel="Medium" AllowAutoDataCaching = "false" height="370px" usedefaultstyle="True" defaultstylemode="Elegant" width="101%" >

<RootTable DataKeyField="EE_Benchmarking_Account_ID" >

<Columns>

<ISWebGrid:WebGridColumn Caption="Request ID" DataMember="RequestID" Name="RequestID">

</ISWebGrid:WebGridColumn>        

<ISWebGrid:WebGridColumn Caption="EE_Benchmarking_Account_ID" DataMember="EE_Benchmarking_Account_ID" Name="EE_Benchmarking_Account_ID" Visible="true">

</ISWebGrid:WebGridColumn>

<ISWebGrid:WebGridColumn Caption="LOACB" Name="LOACB" ColumnType="CheckBox" DataType="System.Boolean" EditType="Checkbox" Width="100px" IsRowChecker="true" >

</ISWebGrid:WebGridColumn>

<ISWebGrid:WebGridColumn Caption="InvByRM" Name="InvByRM" ColumnType="CheckBox" DataType="System.Boolean" EditType="Checkbox" Width="100px" IsRowChecker = "true" >

</ISWebGrid:WebGridColumn>

 <ISWebGrid:WebGridColumn Caption="Payment" Name="Payment" ColumnType="CheckBox" DataType="System.Boolean" EditType="Checkbox" Width="100px" IsRowChecker ="true" >