From the Second Temple period to the end of the first Christian millennium, the text of the Hebrew Bible was studied and preserved in two major centres of Jewish scholarship: Tiberias and Iraq (Bavel). The text-forms preserved in these centres differ one from the other in many hundreds of loci. Moreover, each centre developed its own intricate network of textual notes designed to preserve its respective text-form: so-called Masoretic Notes. Tiberian Masoretic notes appear in hundreds of codices from the Middle Ages and onwards, and continue to be extensively studied. The study of the corpus of Babylonian Masoretic notes, by contrast, remains in its infancy. To date, only a small proportion of this corpus has been identified and edited. Surprisingly, a great many Babylonian Masoretic notes have long lain hidden in plain sight, buried among the Masora Magna and Masora Parva of otherwise Tiberian Bible codices. In this paper I will briefly overview the distinctive features of Babylonian Masoretic notes, before presenting some recently discovered examples of such notes, found in Tiberian Bible codices from the second Firkowich collection.