Carbon dioxide and other substances injected as part of carbon capture and sequestration (CCS) have the potential to migrate beyond the confines of the injection project, creating the potential for trespass. In order for CCS to be viable, legal clarity on the issue of subsurface trespass is required. This Article argues that the challenge of subsurface trespass associated with CCS can be overcome by conceptualizing pore space rights in the storage complex as limited common property with rights of proportionate use. The traditional oil and gas framework of correlative rights can be a valuable model to promote investment, encourage private ordering, and discourage the underutilization of subsurface property for CCS.