There are a number of differences between a library authority file and the ISNI database.
Different goals
As stated on the PCC ISNI Pilot home page, ISNI The ISNI database is not an authority file. Its sole goal is the creation of unique identifiers for public identities (the names by which persons and corporate bodies are publicly known) that are involved anywhere in the life cycle of intellectual and artistic content. (See ISNI FAQ) Therefore, many of the use cases that govern our library authority records (e.g., establishing consistent access points for use in bibliographic descriptions) do not apply.
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As opposed to traditional library authority work, ISNI does not require participants to follow a single standard. The group of contributors is very diverse and includes many non-library sources. Creating an ISNI is solely focused on identification. Names do not need to be unique and are not based on usage. However, it is recommended to use a full form of the name (e.g., forename instead of just an initial, but of course, persons known by their initials, such as T.S. Eliot and D.H. Lawrence, should be recorded with and without initials). A new ISNI record will be matched by an algorithm against the existing database to avoid duplicates, and a fuller form of name is helpful in this process.
All variants of a name that identify a publicidentity are recorded in the same record. While within the system the ISNI contributor codes one name as a 700 the "name" (field 700) and all others as "variant names" (field 400), no “preferred” name is indicated in the public view.
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The goal of an ISNI is NOT to "catalog" the person as can be done in current MARC authorities using the MARC 3XX elements, but to uniquely identify a publicidentity. ISNI therefore only contains the minimal amount of information needed to accomplish this task identify an entity and distinguish it from others (such as as a source, datesdates, titles, related entities, and external links) where necessary – , particularly for common names. An ISNI record does not aim to provide comprehensive information about an entity, but it can include links to web pages and other sources that contain such information.
No earlier/later names for corporate bodies!
ISNI does not recognize the concept of earlier/later names for corporate bodies. treat a new name for a corporate body as a new entity. Different names for linear name changes are all considered variants. A new ISNI is created only created when a change to the structure of the organization occurred, such as a merger or split – essentially causing it to become a different organization.
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