Nimble

The independent exploration and production (E&P) companies pioneered the natural gas industry’s rebirth in North America, but ExxonMobil Corp.’s decision to buy one of the most nimble unconventional producers, XTO Energy Inc., could signal a changing of the guard in the oil patch. The transaction, however, also has focused a brighter spotlight on ExxonMobil, which has few friends in the Democratically controlled Congress, analysts said this week.