Word of a U.S. energy stockpile gain made last week sent crude oil prices falling on Wednesday and Oklahoma energy stocks also had losses.
The climb in stockpiles left investors worried about excess supplies. Reuters reported the benchmarks fell after data from the Energy Information Administration showed crude stockpiles rose by 3.5 million barrels to 441.8 million barrels last week.
West Texas Intermediate crude fell 52 cents or 0.82% to close at $63.15 a barrel on the New York Mercantile Exchange.
Brent crude, the global standard, finished down 54 cents or 0.81% to $66.09 a barrel.
Natural gas prices dropped 18 cents for a 5.02% decline to $3.46.
All but a few of the Oklahoma energy stocks ended the day in negative territory. Most experienced moderate losses. The largest being a more than 3% drop for Mammoth Energy.