Directors

any director ( even if they don't carry the title "director" but they act as though they were to the outside world with the knowledge of the Board ) is fully liable as though they had been correctly appointed.

The Companies Act defines a "director" as "anyone who occupies the position of director, by whatever name called" ie, no matter what their official title, if they act as a director, then they are a director.

Further, the title of "director" applies equally well to "shadow directors" - "those people in accordance with whose instructions the directors are accustomed to act"