The Pergamena Miniata 12 is a roll of parchment over five meters long, transcribed by a single hand in humanistic cursive and decorated on top by the Landriani Master of the Hours with three Sforza coats of arms surrounded by the initials in gold of the name and titles of Ludovico il Moro . The long text contained is the original instrumentum of the sentence issued by Ludovico il Moro on 18 August 1498 in favor of Ludovico Visconti Borromeo versus the sons of the late Giovanni Borromeo (Gilberto, Ludovico, Lancillotto, don Galeazzo and Filippo) for the rights to legacy of Vitaliano Borromeo. At the bottom are the autograph signature of Moro himself and the signum tabellionatus signed by the ducal chancellor and notary Stefano Gusperto da Cremona.

This work, belonging to the permanent collection, is open to the public for conservation reasons only on the occasion of temporary exhibitions.