Contact Lists
08/28/2025
DPV® Licensees Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
Contact Lists
08/28/2025
DPV® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
Contact Lists
08/28/2025
CASS™ Software Manufacturers Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
Contact Lists
08/28/2025
CASS™ Software Manufacturers Cycle O - (Expires July 31, 2028)
Contact Lists
08/28/2025
CASS™/MASS™ Certified Products Guide - All Sections Data Files Cycle O - (Expires July 31, 2028)

This document contains the certified vendors list for CASS™ and MASS™ products for Cycle O.

User Guides
08/28/2025
USPS Verification of Periodicals Advertising Percentage – Alternate Marked Copy Program
Data Files
08/28/2025
Z4 Info File

A downloadable ZIP file containing information related to the Z4 Info File

Contact Lists
08/28/2025
LACSLink® Developers (PDF)

This document contains a contact list of LACSLink® developers.

Contact Lists
08/28/2025
LACSLink® Distributors (PDF)

This document contains the contact list of LACSLink® distributors. 

Data Files
08/28/2025
Early Warning System (EWS002C0.ZIP)

This file is the EWS production file and is updated weekly. This file contains the Early Warning System data file for the CASS™ and MASS™ certification process.