Utilitas publica

Jacobus de Arena († 1320), Commentaria (Lyon 1541) to Tanta s.v. In nomine Domini:

Aut privilegium vel gratiam alicui concedendo, et tunc si obtentu publice utilitatis facit valet, ut infra de evict. l. Lucius (Dig. 21.2.11), si forte a fisco pretium reddetur, licet possessori videatur modicum respectu rei, C. qui ex caus. ser. pro. pre. liber. acci. l.ii. (Cod. 7.13.2) et de rei vendic. Item si verberatum § i. (Dig. 6.1.15).  Nec modo dicetur pati magnam iniuriam, . . . et si contra ius vel utilitatem publicam lege finali, quasi faciat non ut imperator.”

If the prince grants a privilege or a favor to someone and obtains property for public utility, the privilege is valid . . . if however, the grant is contrary to the rights or interests of the public, he does not act as emperor.