Is the 'crazy' M&A market something to worry about? By: CNBC.com News May 20, 2014 at 19:20 PM EDT Global M&A activity has reached levels not seen since 2008, fueling concern about bubbles forming in the market. Read More >> Related Stocks: AT&T Inc Astrazeneca Plc ADR Atlantic Power Corp DIRECTV Facebook Gsk Plc ADR Novartis Ag ADR Pfizer Sentinelone Inc Cl A