Denbury Resources Inc.'s $4.5 billion purchase of Encore Acquisition Co., announced Nov. 1, was one of the biggest deals in the oil patch of late. J.P. Morgan Securities Inc.'s Laurence Whittemore led the deal team advising Denbury, along with colleagues James Roddy, Vean Gregg and Sergei Krylov.

Whittemore -- son of legendary Morgan Stanley banker Frederick Whittemore -- worked on another deal announced the same day: TPG Capital's $500 million investment in Houston natural gas-handling-services provider Valerus Compression Services LP. Whittemore's J.P. Morgan colleague, Doug Petno, and Tudor, Pickering, Holt & Co. Securities Inc.'s David Cunningham also worked on that deal.

J.P. Morgan has had a long relationship with Denbury, most recently advising it on the sale of 60% of its Barnett Shale natural gas assets in northern Texas to EnCap Investments LP-backed Talon Oil & Gas LLC. Whittemore says the latest Denbury deal signifies that oil and gas M&A may be coming back, especially given the amount of cash and the bridge financing available to fund it.

"The Denbury deal suggests that while the market may not be back to where it was 18 months ago, it is in a different place than it was nine months ago, given that a significant acquisition financing commitment was available to help fund the transaction," he says.

Whittemore also advised Houston energy infrastructure services provider Quanta Services Inc. on its $350 million acquisition of natural gas and oil pipeline provider Price Gregory Services Inc. in September, with colleagues Kurt Karges and David Case, and Atlas America Inc.'s $500 million acquisition of 52% of Atlas Energy Resources LLC in April.

Baker and Hostetler LLP's Donald Brodsky, who counseled Denbury with colleague Robert Weible, also has a long-standing relationship with the oil explorer. While at Jenkens & Gilchrist PC, he advised Denbury when it bought Matrix Oil and Gas Ltd. in 2001 for $158 million. Brodsky and Weible also advised Enterprise Products Partners LP's audit, conflicts and governance committee on the company's acquisition of Teppco Partners LP in June for $5.9 billion.

On Encore's side, the sale was a long time coming for Barclays Capital's Greg Pipkin, who was tapped to sell the company while at Lehman Brothers Inc. in the second quarter of last year.

But the subsequent drop in oil prices, the financial crisis and the bank's demise got in the way. He worked with Barclays' Chris Watson and Scott Rogan.

Pipkin has known Encore chairman Jon Brumley for 20 years, including his days at Cross Timbers Oil Co. in the 1980s and Mesa Inc. until its merger with Parker & Parsley Petroleum Co. to form Pioneer Natural Resources Co. in the 1990s. The two talked with other potential buyers up until a week before the deal was announced.

Why did Denbury win? "They were willing to put the most value on the table near term and long term," Pipkin says.

He adds that the fact that Denbury received a financial commitment from J.P. Morgan indicates that dealflow is picking up. "As things have developed over the last 12 to 18 months, people are becoming more confident about the U.S. and global economic recovery, and part and parcel to that is oil prices," he says. "People are able to pay premiums to get transactions done, and there are a handful of global banks that are willing to finance them."

Encore received counsel from Sean Wheeler (pictured above), Stephen Massad and Chris Arntzen at Baker Botts LLP. In 2007 Wheeler counseled Encore affiliate Encore Energy Partners LP on its initial public offering. Last year he advised Wedge Group Inc. on the sale of three oil services units to Pioneer Drilling Co. for $303 million in cash.