(ACB) stock was rising sharply on Tuesday, up more than 9% following a bullish call from Cowen & Co. Aurora Cannabis stock (ACB) has been on a tear in 2019, rising 58.5% since the start of the year. It hasn’t been a straight shot upward for the Canadian cannabis company, but Aurora’s acquisition of Whistler Medical Marijuana drew cheers in January, as did its earnings in February.