When a party filing a patent infringement litigation is not the sole legal owner of the asserted patent, a court may dismiss for lack of standing. Often, the particular language used in the grant clause of an assignment determines whether a co-inventor or other presumptive owner transferred their rights to the asserted patent or merely created an obligation to assign those rights at some unknown time in the future. Agreements that do not explicitly create a present assignment in future rights can only create an equitable claim to ownership, which fails to satisfy the standing requirement.