Bowker manages ISBN assignments the U.S. market. At a November meeting of BISG's Metadata Committee, Purcell noted that overall demand for 978-prefix blocks has diminished inventory, and Bowker expects that it will need to introduce a new 979 prefix in early 2020 to be able to meet demand for blocks of certain sizes.
It's true! New 979 ISBN prefixes are coming! https://t.co/gQPoD9trRz #metadata #metadatamatters
— BISG (@BISG) November 26, 2019
Additional coverage of the shift appeared in Forbes Magazine.