Dynavax Technologies Stock Soars on Buyout Buzz

Biotech stock Dynavax Technologies Corp (NASDAQ:DVAX) is soaring today, last seen up 38.7% at $15.43, after reports that Sanofi (SNY) plans to acquire the company in an all-cash deal worth roughly $2.2 billion. The acquisition is expected to close in the first quarter of 2026. 

Trading at fresh three-year highs, today's bullish gap has DVAX on track for its largest single-day percentage gain since February 2021. The shares are breaking into positive territory for the year, now up 20.8% year to date. 

Short covering could be exacerbating today's gains, as short interest represents a sizeable 12.3% of the stock's available float. At DVAX's average daily trading volume, it would take nearly nine days for short sellers to buy back their bearish positions.