instantiationDigital is used to identify the format of a particular instantiation of an asset as it exists as a digital file on a server, hard drive, or other digital storage medium. Digital instantiations should be expressed as a formal Internet MIME types.

Best practice: InstantiationDigital should only be used to describe the MIME type of the digital file itself. There are multiple options to convey more information about the storage medium or location of the digital file, which are discussed in more detail on the PBCore site.

instantiationDigital can be contained by the elements pbcoreInstantiation, pbcoreInstantiationDocument, and instantiationPart.

Usage: optional, not repeatable.


  • source – optional. The source attribute provides the name of the authority used to declare the value of the element. Different elements will use the source attribute slightly differently. For example, identifier source (required) should be the name of the organization, institution, system or namespace that the identifier came from, such as “PBS NOLA Code” or an institutional database identifier. For other elements, this might be the name of a controlled vocabulary, namespace or authority list, such as Library of Congress Subject Headings. We recommend a consistent and human readable use.
  • ref – optional. The ref attribute is used to supply a source’s URI for the value of the element. Attribute ref can be used to point to a term in a controlled vocabulary, or a URI associated with a source.
  • version – optional. The version attribute identifies any version information about the authority or convention used to express data of this element.
  • annotation – optional. The annotation attribute includes narrative information intended to clarify the nature of data used in the element. Can be used as a notes field to include any additional information about the element or associated attributes


instantiationDigital contains no subelements.

Controlled vocabularies

We recommend you use a MIME type to express your digital file format. MIME media types are available via the Internet Assigned Numbers Authority.

In addition, the UK National Archives’ PRONOM Technical Registry stores commonly used MIME types.


Submit any issues or suggested changes for future schema iterations by creating a ticket in our Github repository.