In HOLLIS, the holdings record contains copy-specific information not contained in the bibliographic record. Holdings record standards and practice are governed by the Harvard University Library policy document, Holdings Records in the HOLLIS Catalog, as modified and extended by Houghton local practice. The HUL Continuing Resources Working Group has prepared MARC 21 Holdings: Examples, a detailed guide to the coding of holdings records for single part monographs, multipart monographs, and serials.
Do NOT change the sub-library of an existing record (i.e. 852, subfield "b"). This practice will interfere with the accurate exporting of records to OCLC. If one needs to relocate an item (usually in the transferring process), suppress the old holding (usually Widener) and create a new one for the new location (Houghton, Theatre, or Poetry).
Detailed instructions on moving holdings and item records can be found in the Moving Records Information pages on the ITS wiki. In a nutshell, if one wants to move a holdings record that has an electronic bookplate or item record with history or an order record on it, send an email to the Associate Librarian for Technical Services that includes the holdings number, item number, and destination bibliographic number. She will do the unlinking and moving.