athenahealth (NASDAQ:

) dropped 10.79% to $113.10 in pre-market trading after Greenlight Capital's David Einhorn said that athenahealth's stock price could decline as much as 80%. Ballard Power Systems (NASDAQ:

) dipped 4.19% to $3.20 in pre-market trading after tumbling 6.44% on Monday. American International Group (NYSE:

) shares fell 3.19% to $51.04 in pre-market trading after the company reported a 27% drop in its first-quarter net income. AIG posted its adjusted earnings of $1.21 per share, versus analysts' estimates of $1.06 per share. YY (NASDAQ:

) shares dropped 2.36% to $60.50 in pre-market trading after the company reported Q1 results. The company's quarterly net income surged 187.2% to RMB183.6 million (US$29.5 million), versus RMB63.9 million.