5. National Oilwell Varco ( NOV) Company profile: National Oilwell Varco is one of the largest drilling rig and equipment suppliers in the drilling industry, including sophisticated offshore, deepwater rigs. Investor takeaway: Its shares are up 16% this month and 24% this year. S&P has its shares rated "buy," with a $98 price target, a 17% premium to its current price. Analysts give its shares 17 "buy" ratings, 11 "buy/holds," and one "hold." 4. Ensco ( ESV) Company profile: Ensco, based in London, owns one of the newest on- and off-shore oil and gas drilling fleets in the industry. It contracts with the world's largest national and international oil companies. Investor takeaway: Its shares are up 17% over the past month and 18% this year. S&P has its shares rated "buy," with a $65 price target, which is a 17% premium to its current price. Analysts expect its earnings will jump 89% this year to $5.87 per share. Analysts give its shares 18 "buy" ratings, 10 "buy/holds," and eight "holds." Ensco was upgraded to Goldman Sachs' Americas buy list last week. 3. Oceaneering International ( OII) Company profile: Oceaneering International, with a market value of $6 billion, is a global provider of equipment and services for deep-water rigs and subsea projects. Investor takeaway: Its shares are up 17% in the past month. On Feb. 13, Goldman Sachs upgraded its shares to its Americas conviction buy list. S&P doesn't have it rated, but its survey of analysts found six "buy" ratings, three "buy/holds," and one "sell." In 2012, analysts expect its earnings will grow 28% to $2.57 per share. 2. Noble ( NE) Company profile: Noble is an offshore drilling contractor for the oil and gas industry worldwide, drilling of oil and gas wells with its large fleet of drilling rigs. Investor takeaway: Its shares are up 20% this month and 27% this year. S&P has it rated "buy," with a $43 price target, a 13% premium to the current price. Goldman Sachs last week upgraded its shares to its Americas buy list. S&P found 20 "buy" ratings, 12 "buy/holds," and nine "holds," in its survey of analysts. Those same analysts expect its 2012 earnings will grow 120% to $3.04 per share. 1. Transocean ( RIG) Company profile: Transocean, with a $16 billion market value, offers offshore contract drilling services for oil and gas wells worldwide. It specializes in deepwater and harsh environment drilling, and also offers project management services. Investor takeaway: Its shares are up 22% in the past month and 28% this year. S&P has its shares rated "hold," due to potential legal and financial liabilities from the 2010 BP oil rig blowout and spill in the Gulf of Mexico. Its 2012 earnings are expected to grow by 155% to $2.73 by analysts, who give its shares 16 "buy" ratings, seven "buy/holds," 15 "holds," two "weak holds," and one "sell." >>To see these stocks in action, visit the 10 Stocks Rallying as Oil Prices Surge portfolio on Stockpickr.