Downstream oil company Delek US Holdings (DK +3.70%) put quite a cap on its trading week with an almost 5% gain in its share price on Friday. Much of this had to do with the company's latest earnings release, disseminated that morning; it featured rather positive developments, such as a flip into the black on the bottom line. An unexpected developmentIn its fourth quarter of 2025, Delek's revenue was just under $2.43 billion; this topped the year-ago result by 2%. More impressively, the company posted a sur ...