Oil's three-day rally to end last week actually put the commodity in a new bull market based on the standard bull market definition of a 20%+ rally that was preceded by a 20%+ decline. Since oil's decline began a couple years ago, there have been three bull markets now. One bull came during the first half of 2015 when the commodity rallied 38%, and another came from late August 2015 through early October 2015 when the commodity rallied 30%.
Oil closed at $32.19 on Friday. It was down another 3% Monday morning, but it will remain in a bull market unless it dips back below $25.75 (a 20% drop from $32.19).