Australia's richest person, mining magnate Gina Rinehart, has sent shock waves through the nation's media with a move on Fairfax, that could give her close to 15 per cent of the group.
Although politicians, unions and media have played down the degree of influence the deeply conservative Rinehart could impose on the group's newspapers, the Government is using her move to push its case for a public interest test on media diversity.
Fairfax newspapers include the Australian Financial Review, the Sydney Morning Herald and the Melbourne Age and, in New Zealand, the Dominion Post and the Press.
Rinehart held 4 per cent of Fairfax before increasing her holding overnight on Tuesday. Brokers acting on her behalf are reportedly seeking to buy 9.9 per cent for A$192 million ($247 million).
This would make her the group's biggest single shareholder.
Rinehart also has a 10 per cent stake in Channel Ten, Australia's third-largest television network, and a seat on the board.
Rinehart's wealth is based on the vast Pilbara mine holdings she inherited from her father Lang Hancock.
This month, she sold 15 per cent of Hancock Prospecting's stake in the Pilbara Roy Hill project to South Korea's Posco, reportedly doubling her wealth to almost A$20 billion.
Rinehart topped last year's BRW Rich List, and Citigroup estimated that she could overtake American Wal-Mart heiress Christy Walton as the world's richest woman and, possibly, eclipse Mexico's Carlos Slim and Microsoft's Bill Gates to become the wealthiest person on the planet.
Concerns over her Fairfax move have centred on the potential influence she could exert on governments. She is a powerful advocate of mining interests and has campaigned against Labor's mining and carbon taxes.
Communications Minister Stephen Conroy said Rinehart's Fairfax play emphasised the need for a public interest test on media diversity.
But Senator Conroy joined Finance Minister Penny Wong, Shadow Treasurer Joe Hockey, and the journalists' union and media analysts in saying that Rinehart was unlikely to be able to force her views on Fairfax editors.
"All that's really changing is that a different wealthy individual is taking a strategic or ownership position in some media," he said.