>You can pass as parameter calling form name. In Init event of form3 you will know caller form name.
>Another possibility is to set global flag with caller form name. You can check this flag on the Load event (if Init is too late for you).

There is also another trick. :)

When you run one form from another, in Init() of the child form you may access the properties and methods of the parent form directly, without passing the parameters - i.e:

thisform.someProperty =_screen.activeform.Name

or

thisform.someControl.Value =_screen.activeform.someControl.Value

This is based on the fact that when the child form runs its .Init() it is not an Activeform yet, because its .Activate() didn't fire so far, so the calling form still stays active at that time.