Protect Unused Numbers from Fraud

Identify inventory and reserved numbers as Do Not Originate (DNO) to reduce brand impersonation, strengthen trust and support industry-wide fraud mitigation.

The Missing Signal in Robocall Prevention

Unused inventory and reserved numbers are a prime target for brand impersonation and illegal robocall activity. Bad actors exploit trusted number ranges to evade detection and damage consumer confidence. Service providers, Responsible Organizations (Resp Orgs) and industry partners need a reliable way to identify inventory numbers that are not intended for outbound calling.

You can’t stop brand impersonation if networks don’t know which numbers should never originate calls.

Introduce Greater Trust with RealNumber® DNO Inventory

RealNumber® Do Not Originate (DNO) enables Resp Orgs, Service Provider ID (SPID) owners and Operating Company Number (OCNs) to proactively identify numbers as DNO, helping the ecosystem recognize and block unauthorized traffic before it reaches consumers.

By contributing DNO inventory data, you help create a stronger foundation for:

Robocall mitigation and fraud prevention
Reduced spoofing of inactive or unused numbers
Improved network integrity and trust
More accurate analytics and call treatment decisions
Industry-wide collaboration against fraudulent traffic

Introduce Greater Trust with RealNumber® DNO Inventory

Simple. Scalable. Trusted.

Helping service providers identify unused inventory numbers and support a more trusted communications ecosystem.

Identify Inventory Numbers

Select inactive, reserved or unused number ranges that should never originate calls.

Contribute DNO Data

Submit DNO number information through RealNumber’s trusted framework.

Enable Smarter Blocking

Support downstream providers, analytics platforms and enterprises with actionable DNO intelligence.

Built for a More Trusted Calling Ecosystem

Trusted Contributor Framework

Enable reliable identification of DNO inventory numbers

Scalable Participation

Designed for Resp Org, SPID owners and OCNs managing large number inventories

Actionable Intelligence

Deliver signals that support blocking, analytics and fraud workflows

Ecosystem Collaboration

Strengthen industry-wide efforts to combat spoofing and illegal robocalls

Trusted Framework Participation Intelligence Collaboration

Help Stop Brand Impersonation at the Source

RealNumber DNO helps service providers proactively identify numbers that should never originate calls — creating stronger signals for fraud prevention and trusted communications.

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