legal address check box in location form

Hi

I am trying to define location from HR Manager-->Work Structures-->location (also available with inventory locations navigation)

I am not able to select the Legal Address check box in the form. Earlier I defined a location with enabling it. But now a message 'Field is protected against update' being displayed.

And without selecting this check box if the location is defined what is the impact? Where does this legal address usage available in oracle applications

Thanks