DYNAVAX Call Vertical / Roll by The Options Insider | Jul 27, 2017 | Unusual Activity Aug 10/15 vertical trades 5000 times for $1.70 with buy-write tag – indicating underlying component.? Paper lifts offer on 5000 DVAX Aug 10.0 calls for $2.45; OI=13k? Paper hits the bid 5000 DVAX Aug 15.0 calls trade $0.75; OI=2320, opening