Antonio Giamberti, known as Antonio da Sangallo the Elder (1455 c.-1534)
In Tuscany he worked as architect in Poggibonsi, Arezzo, Livorno, Florence, and especially Montepulciano, where he built the Church of the Madonna di San Biagio in the shape of a Greek cross as well as several palaces.
Almost certainly his are some annotations in Leonardo's Madrid Ms. II, dating from the years when they were working together at Piombino.
Giuliano Giamberti, known as Giuliano da Sangallo (middle of the 15th century-1516)
Architect, military engineer and sculptor. He was with Leonardo in Milan in October 1492 to present Ludovico Sforza with the project for a grandiose palace.
In Florence he worked on the cloister of Santa Maria Maddalena de’ Pazzi, the sacristy of Santo Spirito and Palazzo Gondi, the latter linked to memories of Leonardo's family. He also worked on the fortifications of Colle Valdelsa, Poggibonsi, Sansepolcro and Arezzo. Lastly, he designed the Medicean Villa at Poggio a Caiano and, starting from 1484, worked on the church of Santa Maria delle Carceri in Prato. This building, with its Greek-cross central plan, constituted a model for the religious architecture of the Renaissance.
Antonio Cordini, known as Antonio da Sangallo the Younger (1483/85-1546)
Architect and wood carver, he worked in Rome in Bramante's circle and collaborated with Raphael. At Orvieto he designed the Pozzo of San Patrizio, which has a forerunner in Leonardo's drawing of a "double winding" stairway found in Ms. B (c. 1487).
