global library cooperative

OCLC, Inc. is a library service and research organization. It helps people find more information and helps libraries work.[4] It was started on July 6, 1967 as the not-for-profit Ohio College Library Center.[5] Later its name changed to Online Computer Library Center as it grew. In 2017, its name changed to OCLC, Inc.[6] 30,000+ libraries in 100+ countries are members of OCLC.[4] The organization was started by Fred Kilgour.[5] Its head office is in Dublin, Ohio, U.S.A. It makes WorldCat, a very big online catalog (a list of books and things like books).

OCLC, Inc.
TypeNonprofit membership cooperative
Founded1967 (1967)
HeadquartersDublin, Ohio,  United States
Area servedWorldwide
Key peopleSkip Prichard, President and CEO[1]
IndustryLibrary services
  • WorldCat
  • Amlib
  • Capira
  • CatExpress
  • Dewey Decimal Classification
  • EZproxy
  • FirstSearch
  • LBS
  • OLIB
  • PiCarta
  • Relais ILL & D2D
  • SISIS-SunRise
  • Syndeo
  • Tipasa
  • TouchPoint
  • UnityUK
  • VDX
  • WebJunction
  • Wise
  • WorldShare
Revenue$217.8 million[3]
Members30,000+ libraries in 100+ countries[4]

OCLC control numbers


OCLC gives a special number (called "OCN" for "OCLC Control Number") to every new record in WorldCat. A record is metadata about books and things like books. Every record has a different number. There are more than a billion numbers, and there are more every day. Old numbers are small and new numbers are big.

OCNs help find books and things like books that do not have ISBNs. Many books from before 1970 do not have ISBNs. OCNs are often used for books in Wikipedia and Wikidata.


  1. "OCLC leadership". www.oclc.org. OCLC. Retrieved 2022-03-10.
  2. "OCLC Qualifying Subscriptions for Membership" (PDF). www.oclc.org. OCLC. February 15, 2022. Retrieved March 11, 2022.
  3. "OCLC Annual Report 2020–2021". Dublin, Ohio: OCLC. December 20, 2021. Retrieved March 11, 2022.
  4. 4.0 4.1 4.2 "About OCLC". OCLC. 16 February 2022. Archived from the original on 2022-03-11. Retrieved 2022-03-11.
  5. 5.0 5.1 Kilgour, Frederick G. (1968). "Initial system design for the Ohio College Library Center: A case history". In Carroll, Dewey E. (ed.). 1968 Proceedings of the Clinic on Library Applications of Data Processing. Urbana, IL: Graduate School of Library Science, University of Illinois at Urbana-Champaign. pp. 79–88. ISBN 9780851570808. OCLC 3269364.
  6. "Certificate of Amendment of the Amended Articles of Incorporation of OCLC Online Computer Library Center, Inc". Ohio Secretary of State. June 26, 2017. Archived from the original on March 21, 2020. Retrieved August 18, 2019. See also: "Amended Articles of Incorporation of OCLC, Inc" (PDF). www.oclc.org. OCLC. June 23, 2017.