An area, measured in acres, that is subject to ownership or control by those holding total or fractional shares of working interests. In a well balanced portfolio of a mature O&G company acreage will represent between 10-20% of its overall portfolio value. The value of the acreage is based on such matters as location, water depth, fluid characteristic, geological conditions, expiration date of license/lease, potential size of discovery if exploration is successful, cost of drilling, etc.