The minimum set of metadata elements, the so-called IMMC core metadata, that is to be used in the data exchange.  IMMC Core Metadata, within the context of the Interinstitutional Metadata Maintenance Committee (IMMC), is defined as: the minimum set of metadata elements relative to the legal decision-making process, to be used in the data exchange between the institutions involved and the Publications Office.

Source: http://publications.europa.eu/mdr/core-metadata/  cited by EU OD