What happened

Shares of oil industry behemoth ExxonMobil (NYSE:XOM) were up 7.4% for the month of September, helped along by rising crude oil prices and broad gains across the oil sector.

However, it wasn't all sunshine and roses for the company. Although it handily beat the S&P 500 for the month, Exxon's stock lagged the overall oil and gas market as measured by the SPDR S&P Oil & Gas Exploration & Production ETF.

A hand holding a gas nozzle in front of a filling station pump

ExxonMobil has managed to outperform its industry, thanks in part to its retail gas sales. Image source: Getty Images.

So what

Exxon's rise correlates pretty directly to improvements in crude oil prices. The price of a barrel of West Texas Intermediate crude was up 9.3% for the month, while Brent crude prices rose 8.2% for September.

As an integrated oil major, and one of the biggest oil companies out there, Exxon tends to have a more stable price than some of the smaller oil and gas drillers. That's been good for shareholders over the past few years as stock prices across the industry have fallen. However, it also means that in months like this, when crude prices are rising, the smaller players tend to gain more than giant Exxon.

Sure enough, that's what we saw in September, as shares of most major independent U.S. oil drillers improved by at least 13%. By contrast, the best-performing integrated majors, BP and Royal Dutch Shell, only turned in 10.7% and 10.4% increases, respectively.

Now what

No news is good news for shareholders of the oil giant. Although its stock price didn't increase nearly as much as some of its smaller peers', that's a sign of Exxon's stability. The company is doing what it's doing, helped along by new discoveries off the coast of Guyana that may pay off handsomely down the road.

Of course, a big improvement in the company's share price is unlikely to come anytime soon unless oil prices move higher. Until then, investors should be content to hang on to their shares, and hope for more months like this one.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.