Source: Noble Energy Inc Presentation Noble Energy Inc [NYSE:NBL] fell by 6.2% after it announced its all-stock purchase of Rosetta Resources Inc [NYSE:ROSE]. Each share of Rosetta Resources will convert into 0.542 share of Noble Energy, and the deal is valued around $2 billion. Noble Energy will take on Rosetta's $1.8 billion debt load, and in return Noble Energy will acquire acreage in two prolific shale plays. Rosetta produced 66,000 BOE/d in Q1 2015 with a 60% liquids production mix from its 56,000 net acre position in the Permian Basin and its 50,000 net acre position in the Eagle Ford. With 1,800 potential drilling locations on that acreage, Noble Energy has grown its growth runway substantially. While Noble Energy paid a hefty 38% premium for the company, Rosetta is down 45% over the past year, which points towards Noble trying to bolster its growth proposition [for when oil prices are higher] through the relatively cheap purchase of quality acreage. The Delaware Basin [where the majority of its new Permian position is located] is one of the lowest-cost shale regions to develop, with companies like EOG Resources [NYSE:EOG] able to break-even [meaning 10% ATROR] when realizing $40 per barrel of oil or even lower in some parts. It varies on where you drill, but the Eagle Ford also has a low break-even cost as well. However, Wall Street apparently doesn't like this deal [at least so far, but things may change] and punished the stock for it. This could be partly due to investors questioning Noble Energy's reasoning considering its sizable operations in the Utica/Marcellus and the DJ Basin [primarily Niobrara and Codell] shale plays and its Gulf of Mexico growth plans. Potentially, this could be a sign that Noble Energy is questioning its own growth runway and bought Rosetta Resources out of fear that its shale assets will run out of oomph. I personally don't think that is the case. I think Noble Energy saw a good value opportunity in front of it and decided to take action. These are two low-cost plays that Noble Energy was able to buy in a way that didn't significantly impact its balance sheet other than the relatively small debt position Noble took on. The deal is expected to close by Q3 2015, and either by then or shortly after I think Wall Street will give Noble Energy more credit over its strategic purchase. Disclosure: Callum Turcan, the author, does not own a position in any of the companies mentioned above. Always do your own due diligence before investing.