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What: Shares of Duncan Energy Partners (NYSE: DEP) soared more than 20% in intraday trading Wednesday after Enterprise Products (NYSE: EPD) offered to purchase the midstream energy firm for $42 per unit.

So what: The proposed deal, in which Enterprise would exchange 0.9545 of its units for each of Duncan's, values Duncan at about $2.4 billion and represents a 28% premium to yesterday's close. The move would allow Enterprise, which already owns 58% of Duncan, to own the company in full and significantly expand its pipeline services.   

Now what: The offer seems like an attractive one for Duncan. In addition to a juicy premium, the proposal gives Duncan shareholders a chance to, as Enterprise CEO Michael Creel puts it, "participate in the future growth of Enterprise, which has a backlog of pending capital projects and a more diverse existing asset base." For those who would rather cash out now, rivals El Paso (NYSE: EP) and ONEOK (NYSE: OKE), both of which sport clearly lower P/Es than Duncan, might be cheap ways to roll that natural gas bet over.

Interested in more info on Duncan? Add it to your watchlist.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days.

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