Does STIR/SHAKEN stop illegally spoofed calls?

Q: Does STIR/SHAKEN stop illegally spoofed calls?

STIR/SHAKEN reduces illegal spoofing by applying a cryptographic signature that allows terminating carriers to verify which service provider signed a call and trace illegal activity back to its source. However, spoofing can still occur before a call is signed, and in those cases the originating service provider must decide whether it has enough information to authorize the caller and assign attestation. If a provider fails to properly vet the caller, an illegally spoofed call may still receive attestation and appear verified at termination. Because STIR/SHAKEN is still evolving in the United States and fraud tactics continue to adapt, it improves traceability but does not fully prevent spoofed calls, meaning enterprises may still experience spoofing related brand and deliverability issues.

🔍 TL;DR

STIR/SHAKEN helps trace and identify illegally spoofed calls by authenticating caller ID, but it cannot fully prevent spoofing, especially when it occurs at call origination or when providers improperly issue attestation.

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📊 Key Facts About Branded Calling

STIR/SHAKEN adds a cryptographic signature to calls to authenticate caller ID information.

Verified signatures reveal which service provider signed and enabled a call.

The framework improves traceback and enforcement against illegal spoofing.

STIR/SHAKEN cannot stop spoofing that occurs before a call is signed.

Originating service providers decide whether to assign attestation levels.

Improper or fraudulent attestation can result in spoofed calls appearing “verified.”

STIR/SHAKEN reduces risk but does not fully eliminate illegally spoofed calls.

STIR/SHAKEN Doesn't Stop Illegal Spoofing

No. STIR/SHAKEN reduces illegal spoofing and improves traceability, but it does not fully prevent spoofed calls.

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How STIR/SHAKEN Reduces Spoofing

STIR/SHAKEN applies a cryptographic signature to calls so terminating carriers can verify which originating service provider signed the call. This makes it easier for carriers and regulators to trace illegal activity back to its source and take enforcement action.

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Why Spoofed Calls Can Still Get Through

Illegal spoofing can occur before a call reaches the signing provider. In these cases:

The originating service provider must decide whether it has enough information to authorize the caller
A provider may improperly issue attestation
A spoofed call may appear verified at termination

Because STIR/SHAKEN relies on provider judgment, it cannot eliminate all spoofing. STIR/SHAKEN is still maturing in the United States. Enforcement practices and fraud tactics continue to evolve alongside the technology.

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Why This Matters to Enterprises

A verified indicator does not guarantee legitimacy. Enterprises that rely only on STIR/SHAKEN may still experience spoofing incidents that damage brand trust and reduce answer rates. Reducing spoofing risk requires stronger identity accountability and number authorization controls across providers, not just call signing.

This content was developed by Numeracle, the leader in Number Reputation Management and Branded Caller ID solutions for enterprises, contact centers, and service providers. As part of our mission to restore trust in communications, Numeracle creates educational resources to clarify complex topics in telecom, compliance, and call delivery.

Our platform empowers organizations to manage branded calling, improve caller id reputation, and stay compliant with evolving regulatory and industry standards. FAQs like this are designed to provide clear, actionable guidance backed by our expertise in verified identity, call labeling mitigation, and spam prevention.

To explore how Numeracle supports trusted and effective outbound communications, visit www.numeracle.com.