LETTERS PATENT. – This name designates, in contrast to the “litterae clausse,” those public documents drawn up in a form different from and simpler than privileges (v.), which were sent or delivered to the recipient without being sealed in any way.
They are far more numerous than letters closed, which began to come into widespread use only at the end of the twelfth century. In these, closure was effected by means of the seal, which secured a cord or strip of parchment wrapped around the document.
BIBL.: A. Giry, Manuel de diplomatique, Paris 1894, pp. 755–780 and 797–98; H. Bresslau, Handbuch der Urkundenlehre, I, 2nd ed., Leipzig 1912, pp. 65–67; A. de Boijard, Manuel de diplomatique française et pontificale, I, Paris 1920, pp. 55–56.