Ardent Leisure says a class action has been served against it in regards to the Dreamworld tragedy that resulted in the death of four people.

The proceedings have been filed by Piper Alderman in the Federal Court of Australia on behalf of persons who acquired Ardent shares between 17 June 2014 and 25 October 2016.

Ardent strongly denies any contraventions of the Corporation Act as alleged and believes the proceedings to be without merit.

Ardent says it intends to vigorously defend the proceedings.

Ardent Leisure shares fell 5 per cent to 48¢ on Thursday.