Cicero to Atticus, written from Astura on the fourth day before the Ides of March 709 AUC — 12 March 45 BC (the manuscript dateline: Scr.\ Asturae iv Id.\ Mart.\ a.\ 709 (45)). A one-day gap in the day-by-day sequence (no surviving letter from 11 March). A single unsectioned paragraph, almost entirely business. Marcianus reports that five of Cicero’s fellow-augurs — Laterensis, Naso, Laenas, Torquatus, and Strabo — have excused him before Appuleius, and Cicero asks Atticus to send each of them a note of thanks in his name.

The rest of the letter is the old Cornificius guarantee, reactivated by the lawyer Flavius’s claim that Cicero stood surety more than twenty-five years ago. Cicero wants Atticus to investigate from the co-sureties’ books, since he had no dealings with Cornificius before his own aedileship in 69 BC; the chronology is at least possible. He breaks off with the characteristic Astura aside — quamquam quid ad me? “though what is it to me?” — before adding the standard riders: send word when Pansa is to set out, greet Attica and care for her with diligence, and greet Pilia. The grief register of the preceding three letters is, in this one, completely suppressed under business: the only mark of it is the parenthesis.