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12/31/2025
CASS™ Certified Products Guide: Vendor/Service Bureaus Licensees Cycle O - (Expires July 31, 2028)
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12/31/2025
CASS™ Certified Products Guide: DSF2® Licensees Data File Cycle O - (Expires July 31, 2028)
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DSF2® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
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12/31/2025
DPV® Licensees Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
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12/31/2025
DPV® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
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12/31/2025
CASS™ Software Manufacturers Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
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12/31/2025
CASS™ Software Manufacturers Cycle O - (Expires July 31, 2028)
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12/31/2025
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.

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DELIVERY - WestPac Area: California 6 District - Wrightwood Post Office and Lytle Post - Resume Operations
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12/29/2025
USPS APIs Terms and Conditions

ACKNOWLEDGEMENT AND ACCEPTANCE. Read this carefully before registering to use the USPS API services. By utilizing the APIs, you hereby ACCEPT ALL of the terms and conditions of this Agreement.