FCC Part 64 CPNI (Customer Proprietary Network Information)
Federal regulations governing how telecommunications carriers protect and use sensitive customer data derived from their network usage.
Customer Proprietary Network Information (CPNI) refers to data that telecommunications carriers collect about their subscribers — including call detail records, location data, service usage patterns, and billing information. Governed by Section 222 of the Communications Act and implemented through FCC Part 64 rules, CPNI regulations restrict how carriers may use, disclose, and protect this data. Carriers may use CPNI to provide the specific service subscribed to but face strict limitations on cross-selling, sharing with affiliates, and third-party disclosure. The FCC has progressively tightened CPNI rules following high-profile data broker incidents, and 2023 enforcement actions have elevated penalties into the hundreds of millions of dollars for major carriers.
Engineering CPNI compliance requires architectural separation of customer data systems. Call detail records, location datasets, and account information must be stored in access-controlled repositories with role-based permissions tied to specific business purpose. Data pipelines that process CPNI for analytics, billing, or network management must implement purpose-limitation controls — preventing engineers from repurposing datasets beyond their original authorized use. Systems that expose CPNI to customer service representatives require authentication workflows including PIN verification or account passcode validation before disclosure. APIs that surface customer records must log every access event with timestamp, employee ID, and stated business reason to satisfy FCC audit requirements.
A critical nuance is the distinction between CPNI and Customer Account Information (CAI) — name, address, and contact data — which falls under different regulatory treatment. Carriers that have merged or acquired other providers must reconcile CPNI policies across legacy billing systems, which often store records in non-standardized schemas. Wireless carriers face additional complexity because location data derived from network signaling can qualify as both CPNI and sensitive location data under FCC rules finalized in 2024. The FCC's annual CPNI certification requirement, due March 1 each year, mandates that carriers file a compliance certification signed by an officer — creating a formal attestation obligation that must be backed by documented technical controls.
We architect CPNI-compliant data systems with purpose-bound access controls, audit-logged disclosure workflows, and automated annual certification evidence packages. Our engineers implement API-level enforcement that prevents CPNI data flows from crossing into unauthorized business contexts, and we build data lineage tooling that maps every CPNI record to its authorized use case.
Compliance-Native Architecture Guide
Design principles and a structured checklist for building software that is compliant by default — not compliant by retrofit. Covers data architecture, access controls, audit trails, and vendor due diligence.