The history of the library is reflected not only in the various names given since 1661, but also in the diverse library book stamps, the imprint of which marks the ownership of the library. The common colour for stamp ink was, and still is, bright red; throughout the history of the library however, reddish brown and blue were also used.
Library book stamps mark all of the library’s books and special materials: they also document the movement of holdings and change of ownerships (which is a valuable aid to the provenance research). Ownership stamps are of great importance, particularly for identifying a missing book or determining its previous owner.
All stamps shown here are valid. The Staatsbibliothek zu Berlin claims ownership of all materials bearing the library’s historic stamps.