NZME and Stuff are pushing to appeal the High Court decision rejecting their merger proposal.

This follows the Commerce Commission refusing to approve the tie-up and the High Court declining the media companies' challenge of this decision.

"The appeal by NZME and Stuff, heard in the High Court in October 2017, was unsuccessful, although the findings of the High Court revealed that the NZCC [Commerce Commission] had significantly understated the quantifiable public benefits from the proposed merger," NZME said in an announcement to the stock exchange this morning.

"After careful review and analysis of the High Court's reasons, the companies continue to believe that the NZCC was wrong in fact and wrong in law to decline clearance or authorisation of the merger," the company said.

The media companies will apply for leave to appeal the High Court decision.

"The High Court's findings increase the range of estimated quantifiable net benefits to the public arising from the transaction to $133 million to $209m, up from the NZCC's estimated range of $41m to $204m; however the High Court still found that these benefits were outweighed by the expected loss of plurality in the media. The appeal will focus on the issue of plurality, it said.

"Given the potentially significant benefits from the merger, NZME is of the view that appealing the High Court decision is in the best interests of NZME, its shareholders and consumers."

The High Court's Justice Robert Dobson Justice Robert Dobson and Professor Martin Richardson, in their decision in December, drew a line between online content aggregators and distributors such as Facebook and Google and news organisations Fairfax New Zealand and NZME in rejecting the publishers' appeal to merge.

Among Justice Dobson and Professor Richardson's findings in the 100-page High Court judgment, they backed the Commerce Commission's decision to turn down a proposed merger of NZME and Fairfax NZ, which was touted as the only way the country's dominant newspaper publishers could stand up to the likes of Facebook and Google eating into their online advertising revenue.

The publishers claimed the online giants would remain a significant competitive constraint on a merged business, something the commission didn't believe in its decision to reject the transaction and that view was upheld in the High Court in Wellington.

The judge and professor said the commission's approach distinguishing a difference between producers of news, and collators and redistributors was relevant and that the regulator was right to exclude the likes of Facebook and Google in assessing the competitiveness of online national news production, which were unlikely to be a "meaningful constraint" on the merged publisher.

"Observed patterns of behaviour suggest that readers are likely to assess content from sites operated both by producers and by collators," the judgment said. "In seeking out reliable original news, visitors to collators' sites are likely to discriminate in their level of attention, placing greater credence and therefore spending more time on items from reputable producers of news."

NZME shares last traded at 84c each.

NZME owns the New Zealand Herald, nzherald.co.nz, a string of North Island newspapers, and radio stations such as Newstalk ZB, The Hits and ZM. Fairfax owns Stuff.co.nz, The Dominion Post, The Press and other newspapers.