Yes, Australians can buy and sell shares of US companies. In order to do so, they would need to open a brokerage account with a firm that offers access to the US stock market. Once they have opened an account, they can buy and sell shares of US companies just like any other investor. However, it is important to note that trading in international markets can be more complex and carries additional risks, so it is important for investors to carefully research and understand the companies they are investing in before making any trades.
“Time makes more converts than reason.” – John C. Bogle