Do you consider yourself a value investor? If so, we ran a screen looking for potentially undervalued oil and gas drilling stocks that may interest you.

We screened a universe of oil and gas drilling stocks for those that appear undervalued relative to the Graham Number. The Graham Number is a measure of maximum fair value created by the "godfather of value investing," Benjamin Graham.

It is based on a stock's EPS and book value per share (BVPS).

Graham Number = SQRT(22.5 x TTM EPS x MRQ BVPS)

The equation assumes that P/E should not be higher than 15, and P/BV should not be higher than 1.5. Stocks trading well below their Graham Number may be undervalued.

*For an interactive version of this chart, click on the image below. Analyst ratings sourced from Zacks Investment Research.*

Do you think these stocks should be trading higher? Use this list as a starting point for your own analysis.

*List sorted by potential upside implied by the Graham Number.*

**1. Oil States International Inc. (NYSE:OIS):** Provides specialty products and services to the oil and gas drilling and production companies worldwide. Market cap at $3.93B, most recent closing price at $69.42. Diluted TTM earnings per share at 8.03, and a MRQ book value per share value at 43.41, implies a Graham Number fair value = sqrt(22.5*8.03*43.41) = $88.56. Based on the stock's price at $66.62, this implies a potential upside of 32.93% from current levels.

**2. National Oilwell Varco, Inc. (NYSE:NOV): **Designs, constructs, manufactures and sells systems, components and products used in oil and gas drilling and production; provides oilfield services and supplies; and distributes products, and provides supply chain integration services to the upstream oil and gas industry worldwide. Market cap at $29.69B, most recent closing price at $66.78. Diluted TTM earnings per share at 5.63, and a MRQ book value per share value at 45.85, implies a Graham Number fair value = sqrt(22.5*5.63*45.85) = $76.21. Based on the stock's price at $64.87, this implies a potential upside of 17.48% from current levels.

**3. Helmerich & Payne Inc. (NYSE:HP):** Engages in the contract drilling of oil and gas wells in the United States and internationally. Market cap at $6.02B, most recent closing price at $55.75. Diluted TTM earnings per share at 5.34, and a MRQ book value per share value at 36.28, implies a Graham Number fair value = sqrt(22.5*5.34*36.28) = $66.02. Based on the stock's price at $53.67, this implies a potential upside of 23.02% from current levels.

**4. Baker Hughes Incorporated (NYSE:BHI):** Supplies wellbore related products, and technology services and systems for drilling, formation evaluation, completion and production, and reservoir technology and consulting to the oil and natural gas industry worldwide. Market cap at $18.11B, most recent closing price at $40.14. Diluted TTM earnings per share at 3.21, and a MRQ book value per share value at 38.38, implies a Graham Number fair value = sqrt(22.5*3.21*38.38) = $52.65. Based on the stock's price at $41.09, this implies a potential upside of 28.13% from current levels.

**5. Atwood Oceanics, Inc. (NYSE:ATW):** Engages in offshore drilling, and the completion of exploratory and developmental oil and gas wells. Market cap at $3.06B, most recent closing price at $45.10. Diluted TTM earnings per share at 4.14, and a MRQ book value per share value at 29.63, implies a Graham Number fair value = sqrt(22.5*4.14*29.63) = $52.54. Based on the stock's price at $44.75, this implies a potential upside of 17.4% from current levels.

**6. Energy Transfer Partners LP (NYSE:ETP):** Engages in the natural gas midstream, and intrastate transportation and storage businesses in the United States. Market cap at $13.29B, most recent closing price at $44.23. Diluted TTM earnings per share at 4.35, and a MRQ book value per share value at 27.38, implies a Graham Number fair value = sqrt(22.5*4.35*27.38) = $51.77. Based on the stock's price at $42.87, this implies a potential upside of 20.75% from current levels.

**7. Gulfmark Offshore, Inc. (NYSE:GLF):** Runs a worldwide fleet of vessels offering marine specialty services to offshore oil and natural gas drilling rigs and platforms. Market cap at $948.02M, most recent closing price at $33.8. Diluted TTM earnings per share at 1.82, and a MRQ book value per share value at 39.4, implies a Graham Number fair value = sqrt(22.5*1.82*39.4) = $40.17. Based on the stock's price at $34.11, this implies a potential upside of 17.76% from current levels.

**8. Martin Midstream Partners LP (NASDAQ:MMLP):** Provides various petroleum products and by-products, and related services in the United States Gulf Coast region. Market cap at $823.82M, most recent closing price at $30.87. Diluted TTM earnings per share at 3.88, and a MRQ book value per share value at 17.46, implies a Graham Number fair value = sqrt(22.5*3.88*17.46) = $39.04. Based on the stock's price at $30.6, this implies a potential upside of 27.59% from current levels.

**9. Newpark Resources Inc. (NYSE:NR):** Provides fluids management, waste disposal, and well site preparation products and services primarily to the oil and gas exploration and production industry. Market cap at $695.91M, most recent closing price at $7.78. Diluted TTM earnings per share at 0.72, and a MRQ book value per share value at 5.86, implies a Graham Number fair value = sqrt(22.5*0.72*5.86) = $9.74. Based on the stock's price at $7.74, this implies a potential upside of 25.88% from current levels.

**EPS and BVPS data sourced from Yahoo! Finance, all other data sourced from Finviz.*

**Disclosure: **I have no positions in any stocks mentioned, and no plans to initiate any positions within the next 72 hours.

**Business relationship disclosure:** Business relationship disclosure: Kapitall is a team of analysts. This article was written by Sabina Bhatia, one of our writers. We did not receive compensation for this article (other than from Seeking Alpha), and we have no business relationship with any company whose stock is mentioned in this article.