The Nasdaq is preparing to roll out 23-hour, five-day-a-week trading for U.S. stocks and ETFs, marking a major shift in how global investors access American markets.The First Step Towards Round-The-Clock TradingThe second-largest stock exchange in the world, with a total market capitalization of $41.23 trillion, is set to file paperwork with the Securities and Exchange Commission on Monday, marking its formal push to extend trading hours and meet the surging demand for nonstop equity trading, according to a ...