Skip Navigation Bar

Fact Sheet

SERHOLD is the National Library of Medicine's (NLM) database of machine-readable serial holdings statements for biomedical serial titles held by U.S. members of the NLM-supported National Network of Libraries of Medicine® (NN/LM®) as well as selected Canadian and Mexican libraries. These holdings statements are linked to NLM's authoritative bibliographic data in LocatorPlusTM. As of July 2012, the database includes over 1.65 million holdings statements for 61,354 serial titles from 2,588 health sciences libraries in the United States, Canada, and Mexico.

Each of the eight Regional Libraries in the NN/LM is responsible for the coordination of updates to SERHOLD®, also referred to as DOCLINE Serial Holdings, for its region. NRC's, National Science Library, the Canadian MEDLARS® Center, coordinates the holdings updates for Canada. NLM distributes holdings data only to participating institutions.

Access to SERHOLD

Only DOCLINE® participants have access to SERHOLD via the DOCLINE Serial Holdings module. Libraries that wish to become DOCLINE participants should review the Eligibility Guidelines for new DOCLINE Libraries. Once libraries become DOCLINE participants, they will receive a USERID and password for the DOCLINE system.

Titles Included

Participants are limited to reporting holdings for serial titles that are in NLM's LocatorPlus database. This database contains over 125,000 serial titles. The database has been augmented by the addition of non-NLM titles held in the NN/LM regions, Canada and Mexico. Titles are reported to NLM with appropriate bibliographic documentation and added to LocatorPlus if they are available for interlibrary loan and provide information needed by health care professionals and health sciences library personnel in the course of their work. Serials designed for recreational reading will not be included. To make requests to add a title to LocatorPlus or to request changes to the bibliographic data, review the Policy Statement on the Addition of Non-NLM Titles to the NLM LocatorPlus Database for DOCLINE Reporting. Since DOCLINE uses holdings records for routing, libraries may only add journal holdings for those titles for which they can provide interlibrary loan.

Updating Holdings Data

DOCLINE can route on holdings information as soon as it is added or modified. NLM encourages all DOCLINE participants to add, modify, or delete holdings for their own library using the DOCLINE Serial Holdings module of the DOCLINE system. To eliminate the need for updating holdings data in both DOCLINE and OCLC, NLM now offers quarterly data transfer from SERHOLD to OCLC via the batch update function. The first SERHOLD to OCLC batch update file, which consisted of holdings for all libraries that had authorized NLM to provide the data to OCLC, was delivered to OCLC in July 2003. NLM provides additional information regarding batch update in the SERHOLD Batch Update FAQs.


Each participating library can produce a list of its own holdings on demand. Participants are also able to view union lists of holdings for libraries in their own library group and in their own state or province. These union list products are updated quarterly.


For questions about Serial Holdings, contact your DOCLINE Coordinator:

Libraries in the United States

NNLM DOCLINE Coordination Office 410-706-4173, or via email at:

Libraries in Canada

The NRC's National Science Library 1-800-668-1222, or via email at:

For general information on NLM services, contact:

National Library of Medicine
Customer Service
8600 Rockville Pike
Bethesda, MD 20894
Telephone: 1-888-FINDNLM (1-888-346-3656)
email: //
NLM Customer Service Form at Contact NLM

A complete list of NLM Fact Sheets is available at:
(alphabetical list)
(subject list):

Or write to:

Office of Communications and Public Liaison
National Library of Medicine
8600 Rockville Pike
Bethesda, Maryland 20894

Phone: (301) 496-6308
Fax: (301) 496-4450