• Besides glosses and other textual annotations, early medieval Latin manuscript commonly feature technical signs, annotation symbols and sigla that reflect readership or provide a framework for interpretation and use. The early medieval Insular book users were particularly keen on using such devices. This article maps the usage of technical signs in a corpus of early medieval Irish manuscripts produced on the Continent or preserved and used there early after the production. In the center of the inquiry are four manuscripts belonging to an Irish scholarly circle associated with Sedulius Scottus. The article concludes that:

    * Insular, and specifically Irish, annotators used a specific repertoire of technical signs;
    * This Insular/Irish repertoire is substantially distinct from the repertoire of technical signs used by Carolingian scribes and therefore allows for discerning books annotated by Insular/Irish users on the Continent;
    * A noticeable difference exists between various identifiable clusters of manuscripts annotated by Insular/Irish users, suggesting that different annotators and circles drew on different parts of the Insular repertoire;
    * The manuscripts from the Sedulius group stand out from among other Irish books produced on the Continent on account of the specific mode of annotation, which seems to have been particular to the circle of scholars that produced them;
    * The Greek Psalter of Sedulius, which contains the subscription of Sedulius Scottus, displays a pattern of sign use distinct from the one found in the manuscripts from the Sedulius group and therefore does not seem related to them;
    * One or two lightly-annotated manuscripts contain traces of annotation in the manner of the Sedulius circle and therefore may reflect activities of the scholars from this scholarly group.