It was named by the Calvinist scholar Theodore Beza because he procured it in the town of Clermont-en-Beauvaisis, Oise, in the Picardie region north of Paris. Beza was the first to examine it, and he included notes of some of its readings in his editions of the New Testament. The later history of its use by editors of the Greek New Testament can be found in the links and references.
The Greek text of this codex is highly valued by critics as representing an early form of the text in the Western text-type, characterized by frequent interpolations and, to a lesser extent, interpretive revisions presented as corrections to this text. Modern critical editions of the New Testament texts are produced by an eclectic method, where the preferred reading is determined on a case-by-case basis, from among numerous variants offered by the early manuscripts and versions. In this process, Claromontanus is often employed as a sort of "outside mediator" in collating the more closely related, that is mutually dependent, codices containing the Pauline epistles: Codex Alexandrinus, Codex Vaticanus, Codex Sinaiticus, and Codex Ephraemi Rescriptus. In a similar way, Codex Bezae Cantabrigiensis is used in establishing the history of texts of the Gospels and Acts.
The Codex Claromontanus contains further precious documents:
Two palimpsest leaves (nos. 162 and 163) are overwritten on fragments of the Phaethon of Euripides, faintly legible under the Christian text. They have been detached from the codex and in the Bibliothèque National are designated Cod. Gr. 107 B.
W. H. P. Hatch, The Principal Uncial Manuscripts Of The New Testament, 1939, The University of Chicago Press, Chicago.
Kurt Aland, and Barbara Aland, The Text Of The New Testament: An Introduction To The Critical Editions and To The Theory and Practice Of Modern Text Criticism, 1995, Grand Rapids, Michigan.
Bruce M. Metzger, The Text Of The New Testament: Its Transmission, Corruption and Restoration, 1968 etc, Oxford University Press. pp. 49 - 51.