Rupert Murdoch has stepped up his attack on tech companies such as Google and Facebook over their increasingly dominant market position, which is eating into the revenues of traditional publishers such as News Corp. and undermining their business model.
In a message to shareholders published in News Corp's annual report released on Wednesday, the octogenarian media tycoon vowed to continue to contest the "abuse of the marketplace" by some big tech companies "wherever possible".
"This is an era where publishers - and the economy and society at large - are affected by the behaviour of a small number of technology companies," Mr Murdoch said.
Without naming the companies, he said the tech giants were "using their dominance to the detriment of many".
News Corp has attacked Google in the past, accusing it of being willing to "exploit its dominant market position to stifle competition" and being a "platform for piracy and the spread of malicious networks".
Newspaper publishers are seeing their revenues eroded as advertising dollars follow consumers to digital platforms such as the social network Facebook, and Google, which have become powerful content distribution platforms in their own right.
News Corp, the New York-headquartered publisher of The Australian, Herald Sun, Daily Telegraph and Wall Street Journal tumbled to a $US643 million ($808 million) loss in the 2017 financial year, after a $US235 million profit in 2016, as it wrote down the value of its Australian and British newspapers and its 50 per cent stake in pay TV operator Foxtel, all of which are challenged by online competition.
News Corp chief executive Robert Thomson said the impairments were made as the company "fully recognised the challenges facing print-based businesses and ensured that the company is fully focused on the future".
The "digital duopoly" had a "responsibility to recognise the provenance of premium content and prevent the proliferation of false news and vile extremist propaganda", Mr Thomson wrote in the annual report.
"It is crucial that algorithms are not used to discriminate against quality journalism and that societies have an informed debate about potential algorithmic abuse."
The media giant has begun working with Facebook and Google on a subscription model "which could help bring more readers to our mastheads and fundamentally change the content ecosystem," he said.