Summary/Abstract
As state legislatures and courts increasingly address the severability of subterranean porosity or storage space, known as “pore space,” from ownership of the overlying land, the time is ripe for an account of what it means for property law to recognize a severed estate in pore space. This Article examines the economic and technological forces driving the severance of pore space and reflects on the consequences, good and bad, of a severed “pore space estate.” As an aid to lawmakers and courts tasked with deciding whether to inaugurate such an interest into their jurisdiction’s property law, the Article searches for lessons in the law’s experience with severed property interests in other natural resources like oil and gas, wind, and water. Three takeaways emerge from the discussion. First, the costs and complications of recognizing a perpetual, freehold estate in pore space counterbalance and may even outweigh the benefits in doing so. Second, many of the costs and complications of a freehold estate would be ameliorated by limiting the duration of pore space interests to the period of their use. And third, prohibiting severance of pore space estates while permitting creation of easements in pore space would do little, if anything, to ameliorate the costs and complications of allowing severance of pore space.