ATP Oil & Gas says Gustav did not cause major harm

Gustav made landfall in southern Louisiana Monday and was widely feared to mirror the damage caused by 2005's Hurricane Katrina. However, the storm's effect turned out to be less than expected.

Gustav moved 12 miles east of ATP's Innovator facility, yet it held its position and initial reviews show no "significant damage," the company said in a statement.

Due in part to the storm, ATP said about 1 to 2 billion cubic feet equivalent per day of gas production will be deferred from the third quarter.

Resumption of total production is unknown, though some facilities have started up again, ATP said.

Shares fell 85 cents, or 3.5 percent, to $23.43 in afternoon trading.