Crude oil futures prices were trading higher for a third day Friday, spurred by stronger July U.S. retail sales data.

Prices showed modest gains in a followthrough from higher equities prices earlier in Europe, which came on the heels of a sharp gain in U.S. share prices Thursday.

European stocks got a firmer footing after regulators in France, Belgium, Italy and Spain imposed a 15-day ban, starting Friday, on short-selling in specific financial stocks to counter volatility on European stock markets. Greece and Turkey had already announced a short-selling ban earlier in the week. Short-selling is a technique used to bet on falling prices.

The Commerce Department reported a 0.5% increase in July U.S. retail sales, near the 0.6% rise expected by economists surveyed by Dow Jones Newswires. June retail sales were up a revised 0.3% compared with an earlier estimate of a 0.1% gain, suggesting that consumer spending, a driving force in the market, may be on the rebound.

Light, sweet crude oil futures for September delivery on the New York Mercantile Exchange was up 72 cents at $86.44 a barrel. Prices were up about 40 cents ahead of the data and posted gains of more than $1 in reaction to the figures before moderating.

ICE North Sea Brent crude for September was up 49 cent at $108.51 a barrel.

Heading into Friday's trading, crude futures had gained 8.1%, or $6.42 a barrel, from Tuesday's settlement of $79.30 a barrel, the lowest since Sept. 29.

"It looks like we've put some kind of a bottom in here after being seriously oversold," said Tom Bentz, director at BNP Paribas Commodity Futures. "But whether we'll continue to recover or roll over again remains to be seen."

September heating oil futures were up 2.42 cents a gallon at $2.9234 a gallon, while September reformulated gasoline blendstock futures were up 0.77 cent at $2.8350 a gallon.