Australia’s federal government and the Tasmanian government said they will provide A$200 million in support for a Rio Tinto aluminium smelter to help safeguard 550 jobs. The move comes less than two months after the federal and NSW governments agreed to inject $2.5bn over 10 years into Rio Tinto’s Tomago Aluminium plant. The smelter had sought support through the federal $2bn Green Aluminium Production Credit scheme but was ruled ineligible. Rio Tinto’s underlying pretax earnings are made up of 56 per cent from iron ore and about 25 per cent from copper.

Nvidia has authorised a US$150 billion share buyback, the largest in corporate history, after announcing a US$80 billion repurchase four months earlier, taking its overall buyback program to US$235 billion. The company reported quarterly profits of US$59.69 billion in late August, more than double the US$26.42 billion a year earlier, as revenue more than doubled to US$96.2 billion. Nvidia said it is now the world’s most valuable public company, with a market capitalisation of about US$5.6 trillion.

Boeing has identified a new 737 MAX software glitch that can disable an automated navigation feature after a missed approach, with 2,422 MAX 8 and MAX 9 jets operating worldwide. The issue is tied to a cockpit software update and can occur when pilots change their planned flight path after aborting a landing attempt, according to the Wall Street Journal. Boeing told airlines in late August it did not consider the problem a safety risk and said engineers are working on a software update to permanently address it. The FAA is investigating, and some major U.S. customers have asked Boeing not to deliver new MAX jets with the affected software, the Journal reported.

Australian building approvals fell 1.1% in May, marking a third straight monthly decline, as approvals for new apartments and townhouses sank 10.4% to 6034, according to fresh Australian Bureau of Statistics data. Total housing approvals rose 2.8% month on month, but the country is tracking about 204,000 new homes in the year to May 31, below the government’s annual target of 240,000. The latest figures also provide an early read on the market’s response to the Albanese government’s budget housing tax changes. State results diverged, with steep falls in Queensland, Victoria and Western Australia offset by a fourth consecutive monthly rise in New South Wales.

Australia’s Treasury has issued a regulatory options paper that would allow structural break-ups of PwC, Deloitte, EY and KPMG, cap partner numbers at 400, and require audit and consulting businesses to be separated. The proposal would also expand the Australian Securities and Investments Commission’s remit, including the power to fine the firms more than A$200 million. The measures follow a series of scandals, including alleged illegal access by EY staff to the Prime Minister’s banking information, whistleblower claims at KPMG over misuse of data, and PwC’s tax-related controversy. None of the Big Four is listed, so the proposed action does not directly affect any listed stocks, commodities or indices.

Australian Prime Minister Anthony Albanese described an alleged bank data breach as a “serious issue”, linked to claims that a former EY employee illegally accessed a politician’s banking information. Assistant Treasurer Dan Mulino released a consultation paper proposing tougher oversight of accounting, auditing and consulting firms, with a focus on conflicts of interest, partnership limits and audit surveillance. EY declined to comment. Two suspects have been charged and the case has been adjourned to August 25.