The first official version reporting Leonardo's birth in Anchiano is found in the renowned Dizionario geografico of Emanuele Repetti (1843-45), supporting what was learned from the owner of the house at the time, the count da Bagnano-Masetti. But it was only during the mid-1900s, during the renovation of the building, that we obtained the first real archival research, by Renzo Cianchi, the first librarian of the Biblioteca Leonardiana. To the Vincian scholar we owe, first of all, the information allowing identification of the Anchiano cottage with the "house for workers and for the lord" present in the da Vinci family patrimony since about 1482. It was bought by Ser Piero, Leonardo's father, probably to turn it into a resting place for those taking the road from Vinci to the Montalbano passes. In the testamentary arrangements of 1506 following the death of Ser Piero da Vinci, which occurred in 1504, the "poderetto" (little farm) of Anchiano was composed of a house in ruins and "una chasa da oste principiata," meaning an innkeeper’s house, just begun: the project seems to have been for a tavern strategically placed along the road to Montalbano. Following the changes of ownership it is clear, however, that the Anchiano house remained for a long time in the branch of the family of the descendants of Guglielmo da Vinci, one of Leonardo’s two half-brothers. Guglielmo lived until his death in the house of Anchiano. It was there that in 1542 he made his will, indicating the church of Santa Lucia in Paterno for his place of burial. The Anchiano house remained in possession of Guglielmo’s lineage until the second generation: one of the nephews yielded the entire farm, so that it went to aggrandize the estate of the grand duke. Finally, in 1645 the property was sold to the family of Count da Bagnano-Masetti, the same family who gave Repetti the 19th-century version of Leonardo’s birth in Anchiano. The series, non-extensive, of passages of ownership of the house that separate the testament of Guglielmo da Vinci from the purchase by Count da Bagnano-Masetti, so well documented by Cianchi, makes clear the origin of the local tradition and explains its power. A tradition, that of the birth of Leonardo in Anchiano, first familial and then local, which matches up with circumstantial elements, certainly not decisive, but surely important, such as the recent analysis of the names of witnesses at Leonardo’s baptism. Several names of the godfathers and godmothers present at Leonardo’s baptism, as reported by the notation penned by his grandfather Antonio, coincide with names taken from the list of parishioners of the community of Santa Lucia a Paterno, according to a document from 1440 recently brought back to light. The personages who attended Leonardo’s baptism, therefore, lived in the neighborhood around the house of Anchiano, which also, as mentioned, was part of the community of Santa Lucia a Paterno.