Gina Rinehart has failed to force a journalist who had written about her family to reveal his sources, after her case was dismissed.

Last year, Mrs Rinehart subpoenaed Steve Pennells from The West Australian to reveal sources used in articles about her family. This year, she placed a similar order on Fairfax Media's Adele Ferguson.

"The journalists declined Mrs Rinehart’s request". Credit:Bloomberg

Lawyers for Mrs Rinehart, a major shareholder in Fairfax Media, argued the information was needed for a private arbitration hearing she was involved with in NSW. The nature of that hearing is confidential.

The journalists declined Mrs Rinehart's request, citing their professional ethics to keep sources confidential.