Walgreens shares being hit down 2.5% to $35.50 and option volume 4x the daily average with 16,000 puts trading to 3,300 calls. Most active strike is the January $37 put with 7,010 contracts traded with a block of 6,500 going at the $2.00 bid price. Prior opn interest in the strike is 13,000 contracts so potentially closing of a position opened on 12/16 when option was trading around 90c. There is fresh buying of 1,000 contracts of the April $33 put. The company reports earnings Monday before the bell.