An explicit bean archive is an archive which contains a beans.xml file:
• with a version number of 1.1 (or later), with the bean-discovery-mode of all, or,
• with no version number, or,
• that is an empty file.
An implicit bean archive is an archive:
• which contains one or more beans with a bean defining annotation, and,
• does not contain a beans.xml with the bean-discovery-mode of none.

A bean archive with empty beans.xml file seems to be both explicit and implicit bean archive.