39 U.S.C. § 401: General powers of the Postal Service

to sue and be sued in its official name; to adopt, amend, and repeal such rules and regulations, not inconsistent with this title, as may be necessary in the execution of its functions under this title and such other functions as may be assigned to the Postal Service under any provisions of law outside of this title; to enter into and perform contracts, execute instruments, and determine the character of, and necessity for, its expenditures; to determine and keep its own system of accounts and the forms and contents of its contracts and other business documents, except as otherwise provided in this title; to acquire, in any lawful manner, such personal or real property, or any interest therein, as it deems necessary or convenient in the transaction of its business; to hold, maintain, sell, lease, or otherwise dispose of such property or any interest therein; and to provide services in connection therewith and charges therefor; to construct, operate, lease, and maintain buildings, facilities, equipment, and other improvements on any property owned or controlled by it, including, without limitation, any property or interest therein transferred to it under section 2002 of this title ; to accept gifts or donations of services or property, real or personal, as it deems, necessary or convenient in the transaction of its business; to settle and compromise claims by or against it; to exercise, in the name of the United States, the right of eminent domain for the furtherance of its official purposes; and to have the priority of the United States with respect to the payment of debts out of bankrupt, insolvent, and decedents’ estates; and to have all other powers incidental, necessary, or appropriate to the carrying on of its functions or the exercise of its specific powers.