Is there a "not equal" in a linq join

I am trying accomplish the LINQ query below but I need a "not equal" instead of equal, so that filteredEmployees has all employees from groupA minus groupB.

List<Employee> groupA = getEmployeeA();
List<Employee> groupB = getEmployeeB();        

var filteredEmployees = from a in groupA 
                        join b in groupB on a.Name equals b.Name
                        select a;