April 21: Unusual Volume Leaders

What follows is a look at stocks in the S&P 500 displaying unusual volume in today's trading session.

Some of the highlights include: Gilead Sciences (GILD), Juniper Networks (JNPR), Altera (ALTR), Huntington Bancshares (HBAN) and Comerica (CMA).

>> S&P Stocks Trading at New 52-Week Highs

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