Indicator positions:
Indicator positions are the first two character positions at the beginning of each variable data field that contain values which interpret or supplement the data found in the field. Indicator values are interpreted independently, that is, meaning is not ascribed to the two indicators taken together. Indicator values may be a lowercase alphabetic or numeric character. A blank (ASCII SPACE), represented in this online help as a #, is used in an undefined indicator position. In a defined indicator position, a blank may be assigned a meaning, or may mean no information provided. The fill character is never used in indicator positions in MARC.
In MARC, a valid NLR value is M Mandatory in both indicator positions for fields that include indicator positions. This includes fields 010 through 8XX and any locally-defined fields within the 010 to 999 range that may be used by a cataloging agency.
Indicator positions are also referred to simply as the indicators, first indicator, or second indicator.
For more information, select: