Former Ryder Cup player Fisher, who captured the title at the London Club in 2008 in the penultimate staging of the event before it dropped off the schedule for six years, shot a six-under-par 65 for a 10-under aggregate of 132.
"It is a course that suits me," the 34-year-old Englishman told reporters at the Bad Griesbach Golf Resort. "I can be aggressive off the tee with the driver and the greens are so pure.
"I've got good vibes with it being the European Open, having won the tournament. I'm delighted it is back on the schedule."
Former U.S. Masters champion Schwartzel signed for a bogey-free 66 while Storm chipped in for an eagle three at the 10th on the way to a 67.
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South Korean An Byeong-hun (65), winner of the BMW PGA Championship at Wentworth in May, was in a tie for fourth place on 133 with Briton Richard McEvoy (67).
(Writing by Tony Jimenez; Editing by Ken Ferris)
