080  Universal Decimal Classification Number (R)

Record Type


Input Standards

Field (Full/Minimal)
1st Indicator  Type of edition
blank character No information provided
0 Full
1 Abridged
2nd Indicator  Undefined
blank character Undefined
Subfields (R=Repeatable  NR=Nonrepeatable) Input Standards (Full/Minimal)
ǂa Universal Decimal Classification number (NR) Mandatory/Mandatory
ǂb Item number (NR) Optional/Optional
ǂx Common auxiliary subdivision (R) Optional/Optional
ǂ0 Authority record control number or standard number (R) Optional/Optional
ǂ1 Real World Object URI (R) Optional/Optional
ǂ2 Edition identifier (NR) Required if applicable/Required if applicable
ǂ6 Linkage (NR) System supplied/System supplied
ǂ8 Field link and sequence number (R) Optional/Optional


Number taken from the Universal Decimal Classification (UDC) scheme. The Universal Decimal Classification was developed from the Dewey Decimal Classification (DDC) scheme beginning in 1895. Since then, the two systems have become very different in arrangement and philosophy.


Repeat field 080 to record multiple UDC numbers assigned to an item.

Multiple call numbers

Certain classification choices are recognized to be local decisions. Multiple call numbers in the same classification scheme in a WorldCat record may be appropriate under certain circumstances. For more information, see 050-099 Introduction to Call Numbers.

1st indicator

Type of edition. Whether the class number is from the full or the abridged edition of the classification schedules. The actual edition number is contained in subfield ǂ2.

blank character

No information provided


Full. Class number is from a full edition.


Abridged. Class number is from an abridged edition.

2nd Indicator

Undefined. The 2nd indicator position is undefined and contains a blank.

blank character



ǂa Universal Decimal Classification number

The UDC number.

080     971.1/.2
080     62-045.43(082.1)(06)
080     821.134.2-1.09"12/14"(045)
ǂb Item number

The item number portion of the UDC number. An item number is a Cutter, date, term, etc., added to a UDC number to distinguish items assigned the same classification number.

080     336.76 ǂb N24d
ǂx Common auxiliary subdivision

The number that qualifies the concept represented by the main UDC number. A common auxiliary subdivision, such as for form (e.g., dictionaries) is attached to a main UDC number preceded or delimited by a facet indicator. Commonly used facet indicators are parentheses, brackets, apostrophes, and hyphens.

080     659.148:656.05:364.272: ǂx (072)(086.8)
ǂ0 Authority record control number or standard number

For information about subfield ǂ0, see Control Subfields.

ǂ1 Real World Object URI

For information about subfield ǂ1, see Control Subfields.

ǂ2 Edition identifier

The edition number, date, or other textual designation of the UDC edition used to compose the classification number.

ǂ6 Linkage

Data that link fields when non-Latin script is entered. This subfield is system supplied and does not appear in OCLC online displays. Do not manually add subfield ǂ6. For more information about subfield ǂ6, see Control Subfields.

ǂ8 Field link and sequence number

For information about subfield ǂ8, see Control Subfields.


For indexing and searching information, see Searching WorldCat Indexes, field 080.


For more information, including content designator history, see MARC 21 Format for Bibliographic Data, field 080.