One of Wall Street's most famous contrarians just made a sizable bet on the AI bubble popping.For many investors, earnings season is the heartbeat of each quarter. This six-week period where a majority of S&P 500 companies report their operating results from the prior quarter provides clear evidence of the health of corporate America and the U.S. economy.However, earnings season isn't the only quarterly event that offers invaluable data to investors. The filing of Form 13Fs with the Securities and Exchange ...