As in many royalty disputes, it is not clear exactly which point of sale is the one on which Feusner's payments should be based – the last sale onto the open market or earlier changes in custody. It's equally unclear whether the expenses being charged to Feusner are incurred before or after that point of sale, or what processes, exactly, fall under the term "gathering." Definitions of that term vary, depending on who is asked. In an email, a spokesperson for Chesapeake declined to say how the company defines gathering.