Storm, who was alone atop the leader board in the first two rounds, was 1-under-par for the day Saturday and 12-under 198 for the tournament.
Storm was joined at the front of the field by Pablo Larrazabal, Gonzalo Fernandez-Castano and Scott Jamieson.
Peter Hanson was a stroke behind the leaders in second place after carding a 3-under-67 at the Hilversumsche Golf Club.
Storm, who shot 63 and 66 in the first two rounds, mainly shot par in the round Saturday, but was tripped up by bogeys on the 13th and 14th holes -- his first bogeys of the tournament.
Sign language interpreter at Mandela service called out as fake on Twitter
N.J. man wakes up from 10-hour sleep with knife in back