org-icalendar-include-todo

org-icalendar-include-todo is a variable defined in `ox-icalendar.el'.
Its value is

nil

Documentation:
Non-nil means create VTODO components from TODO items.

Valid values are:
nil don't include any task.
t include tasks that are not in DONE state.
`unblocked' include all TODO items that are not blocked.
`all' include both done and not done items.

You can customize this variable.