Artificial intelligence investing still has a long growth runway.Following what billionaire hedge fund managers do is possible thanks to the requirement to file a Form 13F every quarter when a fund reaches $100 million or more in assets. Fund managers are required to disclose what securities they hold at the end of each quarter, and then that information is released to the public 45 days later. Although it's far from real time, it allows investors to see where billionaires are seeing opportunities in the ma ...