A sign of a Walgreens store is pictured in Pasadena, California in this December 20, 2013 file photo. Walgreen Co, the largest U.S. Drug retailer, reported a lower than expected quarterly profit and ... more 
A sign of a Walgreens store is pictured in Pasadena, California in this December 20, 2013 file photo. Walgreen Co, the largest U.S. Drug retailer, reported a lower than expected quarterly profit and said it was withdrawing its forecast for 2016 as it moves toward the complete acquisition of Alliance Boots Holdings Ltd. REUTERS/Mario Anzuoni/files (UNITED STATES - Tags: BUSINESS) less 
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Reuters | Photo By MARIO ANZUONI / REUTERS
Tue, Jun 24, 2014 10:21 AM EDT