Download Catalog Record Data (Catfile, CatfilePlus, Serfile)
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Bibliographic records for books, journals and other materials from NLM's collections.
XML Format (NLMXML and MARCXML)All Available Data
(CatfilePlus) Serials Data Only
MARC 21 Format - Baseline DataAll Available Data
(CatfilePlus) Serials Data Only
(Serfile) NLM-Cataloged Records Only
MARC 21 Format - Update FilesAll Available Data
(CatfilePlus) Serials Data Only
(Serfile) NLM-Cataloged Records Only
NLM produces bibliographic records for books, journals and other materials from NLM's collections in NLMXML, MARCXML and MARC 21 formats. These records can be searched at NLM LocatorPlus or the NLM Catalog. Data available for download includes:
CatfilePlus includes cataloging records created by NLM in all formats and all monograph and monograph chapter records created by contributing collaborative partners in the fields of history of medicine, health technology assessment, space, bioethics, and population studies.
NLM Catalog Record Data News
New locally defined subfield in MARC datasets
Effective May 1, 2022, NLM MARC datasets will contain a new locally defined subfield in the 022 field: $7 NLM Local ISSN Qualifier is a textual string describing the format of the resource. NLM previously used $0 for this information, but the MARC standard now defines the $0 as the URI for the ISSN in the $a of the same 022 field. MARC records distributed by NLM will not contain URIs at this time.
New local tag in CatfilePlus data
Starting with the February 2022 file, records in the CatfilePlus dataset may include a 300 $9. This does not affect the CATFILE or SERFILE datasets. If you have any questions, please contact the NLM Support Center.
Base Files for 2022 Posted
The 2022 base files for all MARC, NLMXML and MARCXML products as well as the weekly Catfile distribution file for December 16 are posted. A reminder that any records updated between December 2 and December 16 are only available in the base file.
NLM Catalog Data Update for 2022
NLM’s Cataloging and Metadata Management Section will be undertaking year end processing starting Friday December 3 through Friday December 10 when the 2022 MeSH will be applied to the cataloging records. The last weekly Catfile distribution with 2021 MeSH terms was on December 2. It is expected that weekly Catfile distribution will resume on December 16 which will contain 2022 MeSH. Any record updates made between December 2 and December 16 will only be available in the baseline file. A follow-up announcement will be posted when the baseline files for MARC and XML data are available.
The last monthly CatfilePlus and Serfile distribution with 2021 MeSH was on December 1.
May 24, 2021: upcoming Changes to MARCXML for CatfilePlus and Serfile
With the implementation of the Alma Library Services Platform on June 8, 2021, the MARCXML format for cataloging records in CatfilePlus and Serfile will be updated. The newly generated MARCXML records will contain the "marc" prefix as part of the namespace and will no longer include a carriage return between elements. The records in CatfilePlus and Serfile will reflect the revised MARCXML structure starting with the July 1, 2021 files.
See https://www.nlm.nih.gov/pubs/techbull/mj21/mj21_marcxml_format_change.html for more detailed information.
April 30, 2021: Catfile Distribution Paused Between May 21 and June 8, 2021
In March 2020, we announced our plans to transition from the Voyager Integrated Library System to the Alma Library Services Platform. The system migration is expected to begin May 14, 2021 and be completed by June 8, 2021. Therefore, weekly Catfile distribution will pause after May 20 and will resume distribution on June 10, 2021.
If you have any questions, please contact NLM Support Center.
February 8, 2021: 2021 CatfilePlus and Serfile Available for Download in MARCXML Format
The National Library of Medicine (NLM) would like to remind users that cataloging records in CatfilePlus and Serfile are available for download in MARCXML format. NLM strongly encourages users of our cataloging data to look at and experiment with this format, which is one that is widely used throughout the cataloging community. NLM is moving in the direction of storing and distributing its data in more commonly used formats and standards where possible.
Files for CatfilePlus and Serfile can be downloaded in MARC/XML from Download Catalog Record Data. The naming convention for these files gives the name of the database and the posting date with a suffix of “.marcxml.xml”, e.g. catplus.20200501.marcxml.xml.
April 7, 2020: 2020 NLM Participating in the Program for Cooperative Cataloging’s URI Pilot Project
NLM is participating in the Program for Cooperative Cataloging’s URI Pilot Project whose goal is to engage metadata practitioners in formally applying techniques to further the PCC’s linked data transition. The pilot activities chiefly involve adding identifiers to bibliographic records and/or to authority records. NLM is specifically looking at implications for local and shared practices with regards to names and titles as subjects in 600, 610, 611 and 630 fields of the MARC record. What would be the impact on other libraries if we recode those fields from 2nd indicator 2 of value 2 (MeSH) to 2nd indicator of value 7 (source specified in $2) and add $2 naf and $0 with the LCNAF URI? Making this change would more accurately reflect the source of the names and titles since they are taken from the LCNAF vocabulary and not the MeSH vocabulary.
The test set compiled for this pilot project located at ftp://ftp.nlm.nih.gov/.nlmbib/.catfile/ contains 930 NLM bibliographic records in MARC format. For each of these records, all the 600, 610, 611, 630 fields which were coded as 2nd indicator 2 have been recoded to 2nd indicator 7. $2 naf and $0 with the LCNAF URI have also been added to those fields in the record. We are interested in the impact of this change on local systems and workflows. Please send your comments to the NLM Support Center.
February 28, 2020: MARCXML Announcement
Beginning in April 2020, the National Library of Medicine (NLM) will make its cataloging records in CatfilePlus and Serfile available for download in MARCXML format. This will be in addition to the current distribution in MARC21 and NLMXML. We hope this will encourage wider use of our bibliographic data, as MARCXML is a format widely known and used throughout the library community.
On April 1 the base files for CatfilePlus and Serfiles can be downloaded in MARC/XML from https://www.nlm.nih.gov/databases/download/catalog.html and monthly update files will be available beginning May 1. The naming convention for these files will follow the existing pattern giving the name of the database, the posting date with a suffix of “.marcxml.xml”, e.g. catplus.20200501.marcxml.xml.
NLM welcomes feedback on the availability of this new format. Contact us at: NLM Support Center.
February 4, 2020: 2020 Serfile Reload
The Serfile base XML files have been reloaded on the NLM FTP site on 2/3/2020 after some discrepancies were discovered in the file set loaded on 12/10/2019. If you downloaded the Serfile XML record set in December, NLM recommends replacing it with the set from February. We apologize for any inconvenience.
December 16, 2019: 2020 MeSH MARC 21 Files Available for Download
There has been a slight change to the naming convention for the MeSH-MARC files. The files are prefixed with the posting date in YearMonthDate form, followed by the filename which now includes the MeSH vocabulary year the file contains.
The December files are named:
The January files will be named as follows:
NLM hopes this change will make it clearer to users of MeSH-MARC the data they are receiving.
December 5, 2019: NLM Catalog Data Update for 2020
NLM’s Cataloging and Metadata Management Section will be undergoing year end processing the weekend of Dec. 6-8, 2019 when the 2020 MeSH will be applied to the cataloging records. The last weekly Catfile distribution with 2019 MeSH terms will be on Dec. 5. Subscribers to Catfile can expect larger than normal download files in the batch distributed December 12, which will contain 2020 MeSH.
The last monthly CatfilePlus and Serfile distribution with 2019 MeSH was on December 1. Availability of baseline files for MARC and XML data will be announced in early January.
April 3, 2019: NLM Punctuation Policy
The PCC has announced that beginning April 8, 2019 it will be acceptable for PCC participants to omit final ISBD punctuation from descriptive bibliographic fields in records coded “pcc.” This is an optional choice for individual libraries, records with final punctuation can also be coded “pcc.”
NLM’s policy on final punctuation is not to change any of its current practices. NLM will continue to supply all ISBD punctuation on original NLM records. However, the Library will accept copy records lacking final punctuation and not edit them to add the final periods back into the records. ISBD punctuation between subfields will continue to be supplied by all libraries. Additionally, when a field ends with an abbreviated word, or contains multiple sentences, periods will be retained as in normal grammar rules.
Over time NLM users will see a mix of records with and without final punctuation in the NLM database. It will have no effect on internal or external retrieval of data, nor does it have any impact on internal programs using Voyager data.
August 15, 2018: Format Change for NLM MARC Bibliographic Record Distribution
NLM will begin distributing its MARC bibliographic files (Catfile, Serfile, CatfilePlus, SerfilePlus) in UTF-8 rather than MARC-8 format beginning October 1, 2018. UTF-8 is a more modern encoding format that allows for full representation of character sets outside the roman alphabet.
If if you have questions please contact NLM Customer Support.
January 2, 2018: Completion of the Removal of the General Material Designations from NLM Bibliographic Records
The project to replace the General Material Designation (MARC 21 field 245 $h) on pre-RDA records in the catalog and substitute the appropriate MARC 21 33X fields described in the September/October 2017 issue of the NLM Technical Bulletin has been completed. There will not be a separate distribution of these files. Subscribers who wish to receive updated records with the new 33X fields should download the complete base files which will be made available on January 2, 2018 in MARC and XML formats.
September 27, 2017: Request for Comment Regarding Changes to NLM Cataloging Data
As part of our efforts to prepare our cataloging data for a linked data environment, NLM has determined that some of the MARC coding for our subject fields is not accurate and will not create true triple statements in an RDF environment.
Historically, all MARC 6XX fields used in NLM bibliographic records have been assigned a second indicator of “2,” defined as Medical Subject Headings (MeSH). This is true for data in the 650, 651, and 655 fields which are all taken from the MeSH vocabulary. However, data in the 600, 610, 611, and 630 fields does not come from MeSH, it comes from the National Authority File (NAF). Therefore, coding these fields with a second indicator of “2” is erroneous information. A second indicator of “0” (Library of Congress Subject Headings) would also not be correct. Although LC uses with the NAF form for these subjects, LCSH practices for construction of name and title access points allow additions to these fields that NLM does not permit.
To accurately portray these subject fields the second indicator should be “7” (Source specified in $2) with an accompanying $2 naf added to the 6XX field and NLM would like to make these changes in its files.NLM recognizes that some libraries may rely on the second indicator in the 6XX fields for internal processing. Before making changes to our records we are asking for community input on the impact to your organization or institution if indicators on the 600, 610, 611, and 630 fields were updated from “2” to “7” with the addition of a $2 naf. There may be positive as well as negative impacts. Libraries that are already converting MARC data into triples or have plans to do this in the near future will find that having accurate indicators in the records will more likely allow link resolvers to automatically find the correct data.
Comments about this proposed change to NLM records should be sent to Diane Boehr by Oct. 31, 2017. No changes to cataloging records will be made until the comments are reviewed. Ample notification will be provided before any MARC changes are made.
July 19, 2017: NLM Catalog Data Refreshed
Data in the NLM Catalog was refreshed as of July 20 and contains all updates made to bibliographic records between June 28 and July 19.
July 5, 2017: MeSH URIs added to NLM Catfile
The update to add URIs to MeSH in NLM’s catalog was successfully completed and subscribers to the weekly Catfile data can obtain the updated records from the NLM FTP site as of July 6. Subscribers who don’t want or need these URIs and who prefer not to download such a large set of records can obtain the July 13 distribution which will contain all the records that were updated or created between June 28 and July 12 for reasons other than the URI update.
Subscribers to the monthly CatfilePlus and Serfile data will receive the updated records on August 1. The only option is to receive the entire set. All records distributed going forward in Catfile, CatfilePlus and Serfile will contain URIs associated with the MeSH headings.
Subscribers may receive records that are lacking URIs on some or all of the MeSH. While records are created and updated daily by NLM staff, the program to add MeSH URIs runs weekly, so records that are still in process when the program runs at 1 AM on Wednesday mornings will not have MeSH added until the following week. For CatfilePlus only there may be records with a 65X field with a second indicator other than “2” (which is used to identify MeSH descriptors) or MeSH headings that are not permitted for Cataloger use. These fields will not have URIs.
June 21, 2017: Date Set for Adding MeSH URIs to NLM Catalog Records
NLM will be adding Uniform Resource Identifiers (URIs) to the MeSH subject fields in its catalog records from July 1-4. This project was described in the April 26, 2017 issue of the NLM Technical Bulletin article. LocatorPlus will be unavailable during this period (beginning late afternoon June 30) and the contents of the NLM Catalog will be static from June 30 until sometime during the week of July 17.
The weekly and monthly change files for Catfile, CatfilePlus and Serfile will be extremely large, as all the bibliographic records will be distributed. They will be the same size as the base files that are normally sent out in December (ca. 1.7 million records). The Catfile MARC release will take place on July 6 and CatfilePlus and Serfile releases will occur on August 1. Subscribers to the XML data need to be aware that one minor update has been made to the NLM Catalog DTD to accommodate the URIs.
The revised DTD is available at https://www.nlm.nih.gov/databases/dtd/index.html.
Subscribers to Catfile who are not interested in having URIs for all the MeSH in their bibliographic records and/or those concerned about the size of the file do not have to load the file that will be released on July 6. The July 13 release will contain all records created/changed for other reasons between June 29-July 12.
Subscribers to the monthly files must load the large August files to get the monthly changes.
Note: all files distributed by NLM after July 6 will contain URIs in the 65X fields.
June 19, 2017: Large Catfile with server date of 6/15/17
A very large Catfile release on June 15, 2017 was unexpectedly and mistakenly sent to subscribers. If your institution has already loaded the file that is fine, but if you have not already imported the file, you can just skip the large file from June 15 and get the needed updates in the June 22 file. NLM apologizes for any inconvenience.
May 2, 2017: Adding MeSH URIs to NLM Catalog Records
As part of the library community's effort to prepare current bibliographic data for the eventual transfer to a linked data environment, NLM will be adding Uniform Resource Identifiers (URI) to the MeSH subject fields in its catalog records. The URIs will be recorded in the $0 of the MARC 21 650, 651 and 655 fields and provide a machine actionable link to the MeSH RDF records for each subject.
October 1, 2016: Termination of Licensing Requirement
The NLM Data License has been replaced by Terms and Conditions. No registration is required to access data available from NLM's FTP servers. Users will not be required to renew a license agreement at the end of the year.
Last Reviewed: February 25, 2022