Malcolm Bligh Turnbull AC (born 24 October 1954) is an Australian former politician and businessman who served as the 29th prime minister of Australia from 2015 to 2018. He held office as leader of the Liberal Party of Australia. Since retiring from politics, Turnbull has become an advisor to Kasada, an Australian cybersecurity start-up. He has been critical of the direction of the Liberal Party, and has joined with fellow former prime minister Kevin Rudd in criticising the dominance of Rupert Murdoch's News Corp in Australian political debate.