Most shorted stocks ahead of earnings

While earnings season often provides companies an opportunity to tout their latest successes, some firms are expected to fall flat on their face.

Of those companies announcing earnings this week, subprime lender World Acceptance has been the most shorted stock ahead of quarterly announcement, followed closely by IT firm Neustar, according to data from Markit.

With almost a third of its shares outstanding on loan, World Acceptance is actually less shorted than in April when it had over 40 percent on loan, according to Markit.

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Markit also found that the company seeing the largest jump in shorted stock is oil rig leaser Hercules Offshore. The company "has seen its short interest more than double in the last four weeks after announcing the loss of two forecasted contracts, which had many investors questioning the strength of the company's backlog of work," Markit analyst Simon Colvin wrote.

And while shorts are piling into Hercules Offshore and biofuel marketer and producer Pacific Ethanol, Markit found that Hawaiian Holdings—parent of Hawaiian Airlines—is seeing the biggest decrease in its shares on loan.

Here's the rest of Markit's list:

% Shares Outstanding On Loan
1 Month % Change
Earnings Date
World Acceptance Corp WRLD 30.9 1% Consumer Finance 7/22/2014
Neustar Inc NSR 30.4 -7% IT Services 7/23/2014
Cliffs Natural Resources Inc CLF 29.5 3% Metals & Mining 7/25/2014
Irobot Corp IRBT 29.3 -2% Household Durables 7/22/2014
Jetblue Airways Corp JBLU 27.6 1% Airlines 7/24/2014
Chemed Corp CHE 26.7 0% Health Care Providers & Services 7/23/2014
Exact Sciences Corp EXAS 25.0 -7% Biotechnology 7/22/2014
Janus Capital Group Inc JNS 21.4 2% Capital Markets 7/23/2014
Wesco International Inc WCC 20.2 3% Trading Companies & Distributors 7/24/2014
Hercules Offshore Inc HERO 20.1 108% Energy Equipment & Services 7/23/2014
Theravance Inc THRX 18.9 5% Pharmaceuticals 7/25/2014
Acacia Research Corp ACTG 17.6 -5% Professional Services 7/24/2014
Pacific Ethanol Inc PEIX 17.4 34% Oil, Gas & Consumable Fuels 7/24/2014
Healthways Inc HWAY 16.1 -9% Health Care Providers & Services 7/23/2014
Verisign Inc VRSN 15.9 4% Internet Software & Services 7/24/2014
Hawaiian Holdings Inc HA 15.6 -9% Airlines 7/22/2014
Titan International Inc TWI 15.0 -7% Machinery 7/24/2014
Abaxis Inc ABAX 14.8 2% Health Care Equipment & Supplies 7/25/2014
Cabela's Inc CAB 14.7 -5% Specialty Retail 7/24/2014
Proto Labs Inc PRLB 14.5 12% Machinery 7/24/2014
Markit Equities Research

Internationally, Finnish construction company Yit and Swiss tech firm Logitech were the most shorted European stocks with 12.1 percent and 11 percent of outstanding share on loan, respectively.

In Asia, the bears are out on semiconductors, with Advantest and ASM Pacific Technology both in the top three most shorted stocks, according to Markit.

This earnings season may prove tough for those holding shorts. Some 67 percent of S&P 500 companies that have already reported this quarter announced revenue above analyst expectations, and 68 percent have beaten on earnings, according to data from Thomson Reuters.

This exceeds long-term averages in Reuters figures of 61 percent beating on the top line and 63 percent beating on earnings.

The most shorted stock in the S&P 500 is GameStop, followed closely by Cablevision Systems, according to FactSet.

—By CNBC's Everett Rosenfeld