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Open Metadata Service: Home

Descriptions and modes of access for resource discovery-related metadata

Purpose of Guide

The Yale University Library (“the Library”) assigns structured metadata to describe our collections and make them discoverable through local catalogs and search engines such as Quicksearch, Archives at Yale, and Yale Digital Collections.
As much care as we put into our local discovery tools -- and we certainly encourage you to use them -- we recognize that the best uses of our data may come from those who remix and re-publish these data in novel and interesting ways. We therefore welcome efforts to devise new ways of exploring and accessing our collections and classification systems, including building one’s own discovery tools and services.
Toward this end, we release our metadata as openly and widely as possible. We avoid placing restrictions on reuse, except in cases of ethical, contractual or legal obligations, e.g., metadata received on condition that we not share them further, or metadata for which sharing might compromise user privacy. This service is in line with Yale’s broader support for open access, including the high resolution digital images made available through our cross-collection discovery portal, and open scholarly communication enabled through our EliScholar platform.
Most metadata generated by the Library will be open, by default, for sharing and reuse, and released with a public domain Creative Commons CCO license. Records derived from the shared OCLC WorldCat database are made available as Open Data Commons ODC-BY with a credit to OCLC. In all other cases, we will attempt to negotiate terms that allow maximal sharing and reuse, as we do with our locally produced records, and label them accordingly.


Modes of Access

The Library intends to make it as easy as possible to download or query our data, both by human agents and machines. Below, we provide brief descriptions and access options for currently available datasets. These are followed by datasets under current review, followed by datasets of possible interest for the future.

Datasets currently available   

Bibliographic datasets

  • Orbis (Yale catalog) bibliographic, holdings, and authority records  
    • Bulk MARC downloads: The following record sets must first be extracted from archived compressed file with these filename patterns: mrc_yyyymmdd_all.tar.gz (complete set, refreshed weekly) and bib_[usage rights category]: yyyymmdd_update_nnn.mrc
      • Yale-originated records (MARC21), bibliographic records, interfiled with holdings records, shared under Creative Commons CC0 license CC0, updated daily and refreshed every Sunday, identified by the filename pattern: bib_yyyymmdd_all_yale_000.mrc, where 000 represent sequential batch file number
      • Worldcat-derived records (MARC21), bibliographic records interfiled with holdings records, released under Open Data Commons ODC-BY, updated daily and refreshed every Sunday, identified by filename pattern bib_yyyymmdd_all_oclc_000.mrc
      • Other records (MARC21), independent of Yale and WorldCat, where sharing is permitted; bibliographic records interfiled with holdings records, identified by filename pattern bib_yyyymmdd_all_other_000.mrc
      • Authority records (MARC21), shared as public domain resource by the Library of Congress, that are associated with Orbis bibliographic records, updated daily and refreshed every Sunday, identified by filename pattern aut_yyyymmdd_all_dlc_000.mrc 
    • Z39.50 protocol​ (MARC, XML, OAI-PMH; updated dynamically)
    • BIBFRAME XML bulk downloads. Sharing is permitted. (updated when new records sets are available via SHARE-VDE)

Archival datasets

Encoded Archival Description (EAD) files are shared according to the CC0 1.0 Universal license

Datasets under consideration or review 

  • Orbis bibliographic records 
  • Morris (Law Library catalog) 
    • MARC bulk downloads

Datasets of possible future interest

  • Archives at Yale (API access)
  • Audio-visual collections metadata (Avalon Media Systems)
  • ContentDM (e.g. Yale Daily News Archive)
  • EliScholar (BePress Digital Commons)
  • Digital Collections (FindIT)  
  • MORRIS (Law Library Catalog API access)​
  • Beinecke publicly accessible digital collections 
    • DPLA API   
    • Connecticut Digital Library
  • Yale University web archives

Modes of Access