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(Adds background on IPOs, Antero reserves)
By Michael Erman and Olivia Oran
NEW YORK, May 6 (Reuters) - Antero Resources, an oil andnatural gas company controlled by Warburg Pincus LLC, ispreparing for an initial public offering that could value it atas much as $10 billion, three people familiar with the mattersaid on Monday.
The Denver, Colorado-based company has hired Barclays Plc, JP Morgan Chase & Co and Citigroup Inc to lead the deal, two of the people said on condition ofanonymity because the plans are private. The company could cometo the stock market later this year, they added.
Barclays, Citigroup and Warburg declined to comment.JPMorgan could not be reached for comment.
Antero reported adjusted earnings before interest, tax,depreciation and amortization of $434.3 million in 2012, up from$340.8 million in 2011.
The company has around 311,000 acres in the Marcellus Shaleformation in West Virginia and Pennsylvania as well as 92,000acres in Ohio's Utica Shale.
Antero believes that most of their acreage in the Marcellusholds natural gas liquids, which tend to be worth more than"dry" gas.
The company said its Utica acreage sits in a region that itbelieves holds natural gas liquids. The Utica shale is anemerging region that has attracted the interest of big oilcompanies like Exxon Mobil Corp and Chevron Corp.
Antero's said earlier this year that its proved, probableand possible reserves were 26.1 trillion cubic feet equivalentof gas and oil.
According to Thomson Reuters data, there have been onlythree U.S.-listed IPOs in the energy and power spaceyear-to-date that raised proceeds of $973 million. That's downfrom eight companies which raised $2.2 billion during the sametime last year.
Warburg and other investors including energy-dedicatedprivate equity firm Yorktown Energy Partners and Lehman BrothersMerchant Banking Group initially invested $260 million in Anteroin 2003. Four years later, the consortium led a $1 billionequity investment in the company.
Private equity firms are increasingly looking to publicmarkets in 2013 to profitably exit their investments as thefrothy stock market has buoyed the value of companies public andprivate alike. (Reporting By Michael Erman and Olivia Oran; Additionalreporting by Greg Roumeliotis; Editing by Tim Dobbyn)
