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The Superintendent of Documents Classification System: An Explanation of the SuDoc Numbers

The Porter Henderson Library receives federal document materials in paper, microfiche, CD-ROM, and video format. The Library uses the Superintendent of Documents (SuDocs) classification system to organize these materials. The SuDocs classification system is designed specifically for United States government documents and is assigned by the office of the Superintendent of Documents (SuDocs) of the Government Printing Office.

Unlike most classification systems, SuDoc numbers are not based on subject. The system is straightforward, on the surface – A for Agriculture, C for Commerce, D for Defense, E for Energy, GP for Government Printing Office, T for Treasury Department, and so on. The logic behind the SuDocs system is the grouping of subordinate units with the parent organization so that each full notation reveals the responsible issuing agency for the type of publication being classified. This type of system is called a provenance system – it organizes publications based upon issuing agency.

There are exceptions to the straightforward letters, of course: Y 1; call numbers are general publications of Congress – House and Senate Documents and Reports,Y 3; call numbers are independent boards and commissions, and Y 4 call numbers are House and Senate Committee hearings and publications.

Because the classification system is based on the current organizational status of the government author, it changes as the organizational structure of the federal government changes. Thus, publications of some issuing agencies may be located in as many as three different places in the system.

SuDoc numbers can be quite simple or very complex. For instance,

What you really need to know

However, before going into greater detail about SuDoc numbers we must focus on the three things you really need to know:

SuDocs is NOT a decimal system

The number after the period is a WHOLE number. (There is always a space between letters and numbers in the SuDoc system — unless there is punctuation between them. Punctuation in a SuDoc number always acts as a divider, not as a decimal point.)

Remember: Years, Letters, Numbers!

If the call number is the same to a certain point, then varies, the order is: Years, Letters, Numbers. Until the year 2000, the first number was dropped from years, so those years have 3 digits. Beginning with the year 2000, years will be 4 digits.

Correct Call Number Order

Example 1
A 1.35:999 (year, 3-digit)
A 1.35:2004 (year, 4-digit)
A 1.35:R 42/995
A 1.35:R 42/2
A 1.35:321

Example 2
EP 1.23:998
EP 1.23:A 62
EP 1.23:91-44
EP 1.23:600/998-103
EP 1.23:600/R-98-23

Slashes and Dashes

If the class stem (the numbers before the colon) has numbers slashed onto the base number, the base number comes first, followed by the slashed numbers in order. The same rule applies to numbers dashed onto other numbers or letters.

Correct Call Number Order

Example 1
C 3.186:
C 3.186/2:
C 3.186/7:
C 3.186/7-3:
C 3.186/9:

Example 2
EP 1.23:998
EP 1.23/A:
EP 1.23/A-2:
EP 1.23/2:
EP 1.23/2-2:

Filing Rules for U.S. Government Publications at Porter Henderson Library

(because if you know “the rules” you can find the document)

Filing rules differ from library to library. These are the rules we follow at the Porter Henderson Library.

Before the colon:

In general, the order of filing punctuation before the colon is:

Parts of a SuDocs Class Number

To read a SuDoc number, you must begin by recognizing the three major elements: author symbol, series designation, and book number. SuDoc numbers are divided, usually at the colon, into two parts – the class stem (composed of the author symbol and the series designation) and the book number – which then combine to make a complete SuDoc number. We’ll use I 29.6/6:F 75/988 as an example.

Class Stem

All SuDoc numbers begin with one to three letters. Each department or independent agency of the United States government is assigned a letter or combination of letters of the alphabet based on the name of the agency. For instance, the Commerce Department has been assigned the C. The Defense Department uses the D, the Justice Department the J, etc. X and Y are reserved for Congress. Newer agencies tend to be assigned multi-letter designations – the newly independent Social Security Administration, for instance, has been assigned SSA. The new cabinet-level department, the Department of Homeland Security, has been assigned HS.

Therefore, in our example, we know from the “I” that the Department of the Interior issued the publication.

The author symbol of the class stem is the letter and number up to the period. Subordinate bureaus within each agency are assigned numbers beginning with 2. The number 1 is reserved for the parent organization. Thus, “I 29.” is the author symbol in our example and stands for the National Park Service, the 28th bureau of the Department of the Interior. The bureau number is then divided from the rest of the SuDoc number by a period.

Series Designations

Following the period, each series issued by that bureau is also assigned a number. New series which are closely related to an existing series are “attached” to the existing series by putting a slash after the existing series number and then adding another letter or number. For instance:

Sometimes the number after the period can be rather complicated, involving both slashes and dashes to relate series to each other. The class stem then usually ends with a colon.

In our example, I 29.6/6: stands for the National Historic Site Information Circulars series from the National Park Service of the Department of the Interior.

The following numbers are assigned for the types of publications common to most Government offices:

  1. Annual reports
  2. General publications (unnumbered publications of a miscellaneous nature)
  3. Bulletin
  4. Circulars
  5. Laws (administered by the agency and published by it)
  6. Regulations, rules, and instructions
  7. Releases
  8. Handbooks, manuals, guides
  9. Bibliographies and lists of publications
  10. Directories
  11. Maps and charts
  12. Posters
  13. Forms
  14. Addresses, lectures, etc.

A list of all the current series available from the United States Government Printing Office can be found in the List of Classes of United States Government Publications Available For Selection by Depository Libraries. An historical list of all the series that have been created by the Government Printing Office can be found in Andriot’s Guide to US Government Publications (Documents/Reference Z1223.Z7 A572)

Book Number

After the class stem, each individual issue or publication in a series is assigned a unique identifier, called a book number, following the colon. Serials, numbered monographic series, and unnumbered monographs, all have different types of identifiers.

For unnumbered monographs, the identifier is usually an alphanumeric Cutter number (like those used for the book number in Library of Congress and Dewey Decimal classification) based on the subject.

For numbered series, the identifier usually is:

At one time, GPO designated revisions of numbered publications by a slash and additional numbers beginning with “2.” For example: A 1.35:381/2. This practice proved to be confusing, so now the last three numbers of the year of revision are used.

A - Department of Agriculture
22 - Office of Statistics
.1 - Genre: annual reports
831/ - Publication number
2000 - Year of revision

GPO may add -rev for a slight revision. The addition of -2 means the item is a reprint.

For serials (magazines, journals, annual reports, etc.), the identifier is usually:

Putting It All Together

Returning to our original example, we have learned that I 29.6/6:F 75/988 stands for the 1988 edition of Ford’s Theater and the House Where Lincoln Died in the series National Historic Site Information Circulars from the National Park Service of the Department of the Interior of the United States of America.

For More Information …

… and “practice” understanding the SuDocs classification numbers, use the Online tutorials below:

FDLP and Texas Depository logos Government Documents Home

Superintendent of Documents Classification System
A Agriculture Department
AE National Archives and Records Administration
B Broadcasting Board of Governors
C Commerce Department
C 3 Census Bureau
CC Federal Communications Commission
CR Civil Rights Commission
CS Civil Service Commission
D Defense Department
E Energy Department
ED Education Department
EP Environmental Protection Agency
FA Fine Arts Commission
FCA Farm Credit Administration
FEM Federal Emergency Management Administration (became part of Homeland Security — HS)
FHF Federal Housing Finance Board
FMC Federal Maritime Commission
FM Federal Mediation and Conciliation Service
FR Federal Reserve System Board of Governors
FT Federal Trade Commission
FTZ Federal Trade Zone Board
GA Government Accountability Office (formerly: General Accounting Office)
GP Government Printing Office
GS General Services Administration
HE Health and Human Services Department
HH Housing and Urban Development Department
HS Homeland Security Department
I Interior Department
I 19 U.S. Geological Survey
IA U.S. Information Agency
IC Interstate Commerce Commission
ID U.S. Agency for International Development
ITC International Trade Commission
J Justice Department
JU Judiciary (Courts of the United States)
L Labor Department
LC Library of Congress
LR National Labor Relations Board
MS Merit Systems Protection Board
NA National Academy of Sciences
NAS National Aeronautics and Space Administration
NC National Capital Planning Commission
NCU National Credit Union Administration
NF National Foundation on the Arts and the Humanities
NS National Science Foundation
OP Overseas Private Investment Corporation
P United States Postal Service
PE Peace Corps
PM Personnel Management Office
PR President of the United States
PREX Executive Office of the President
PRVP Vice President of the United States
RR Railroad Retirement Board
S State Department
SBA Small Business Administration
SE Securities and Exchange Commission
SI Smithsonian Institution
SSA Social Security Administration
T Treasury Department
T 22 Internal Revenue Service
TD Transportation Department
TDA U.S. Trade and Development Agency
VA Veterans Administration
X and Y Congress
Y 1 House and Senate Reports and Documents
Y 4 Congressional Committee Hearings