svcutil.exe redundant proxy classes

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WCF

VS2010

WCFServices

I'm writing a .NET 4.0 app and have control over both the WCF service and client.
I'm using svcutil to generate proxy classes for my services, combining several services.
svcutil /o:.\ServiceProxies\NavigatorServiceWCFProxy.cs /ct:System.Collections.Generic.List`1 /namespace:*,FIS.Navigator.Common.NavigatorService /noconfig http://localhost/NavigatorService/NavigatorService.svc?wsdl
It generated two class look like:
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.CodeDom.Compiler.GeneratedCodeAttribute(System.Runtime.Serialization, 4.0.0.0)]
[System.Runtime.Serialization.DataContractAttribute(Name=RequestBase, Namespace=http://schemas.datacontract.org/Navigator/Base)]
public partial class RequestBase : object, System.Runtime.Serialization.IExtensibleDataObject
{

}
[System.CodeDom.Compiler.GeneratedCodeAttribute(svcutil, 4.0.30319.1)]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute(code)]
[System.Xml.Serialization.XmlTypeAttribute(Namespace=http://schemas.datacontract.org/Navigator/Base)]
public partial class RequestBase
{
}
If we add a service reference only one partial class is generated in reference.cs Why it is creating two Classes?
How to generate only one partical class using svcutil ?