More changes are coming to the System for Award Management (SAM.gov). The registration site for companies interested in doing business with the federal government.
One of the looming changes includes the transition from DUNS number to Unique Entity Identifier (UEI). This recent release from GSA Integrated Award Environment can help answer questions about the change.
https://interact.gsa.gov/blog/what-do-i-need-know-about-new-unique-entity-id-samgov