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July 22, 2021 – San Francisco

Twilio Achieves Full Compliance with STIR/SHAKEN Protocols to Combat Illegal Robocalls

 By authenticating 100% of its calls, Twilio protects end users against unwanted communications and brings trust back to the phone call

SAN FRANCISCO, July 22, 2021 — Twilio (NYSE: TWLO), the leading cloud communications platform, has achieved full compliance with the STIR/SHAKEN protocol, intended to ensure that the phone calls transmitted via its platform are legitimate and authenticated. All of Twilio’s calls will be stamped with an approval attesting to the fact that terminating service providers and end users can trust that the call is not illegally spoofed. 

STIR/SHAKEN (Secure Telephone Identity Revisited/Signature-based Handling of Asserted information using toKENs/) is a set of protocols developed by the Internet Engineering Task Force (IETF), the Alliance for Telecommunications Industry Solutions (ATIS) and the SIP Forum that verifies not only whether a caller has the right to use a calling number but that the caller is a known entity by the originating party. In addition, call analytic treatment can help inform end users of a caller’s identity by adding additional information to determine if the call is wanted or not. Calls have to be wanted; if they are determined to be potentially illegitimate based on call analytic treatment, end users will be warned ahead of time by some type of an indicator on the screen when the call arrives. Depending on what type of handset and network the individual is using, calls might arrive with a green check mark to confirm the number is not illegally spoofed, or the handset could label a call with a warning like “Spam Risk” to alert the consumer that the call could be unwanted or illegitimate. 

Twilio also announced that it has enrolled in the Federal Communications Commission’s Robocall Mitigation Database through which voice service providers are required to inform the agency of their robocall mitigation efforts. Participants in the telecommunications ecosystem must indicate if they are using STIR/SHAKEN protocols on originating calls. If a service provider cannot sign all calls with the protocols, they must submit their own plan to the FCC on how they will block or mitigate illegal robocalls. Non-participants also risk losing their ability to originate calls and potential enforcement actions against them by the FCC if they are found to be hosting illegal robocalls on their networks.

These actions continue Twilio’s momentum for bringing trust back to the phone call. Furthering this effort, Twilio recently joined T-Mobile and other telecommunications partners to successfully test what is believed to be the first wireless call to combine authenticated Caller ID and Rich Call Data (RCD), powered by the STIR/SHAKEN framework and protocols. In December, Twilio joined Comcast and other partners to complete a test of the first IP-based call that also combined authenticated caller ID with Rich Call Data (RCD) via the STIR/SHAKEN protocols. Twilio is also a member of USTelecom’s Industry Traceback Group to help identify, investigate and prosecute the bad actors behind illegal robocalls. Finally, Twilio is participating in the state Attorneys General public/private partnership with the telecommunications industry to share information supporting their efforts to bring robocall criminals to justice.

Twilio is continuing its engagement on the STIR/SHAKEN front by participating in numerous panel discussions at this week’s 2021 STIR/SHAKEN Virtual Summit hosted by the SIP Forum.


Millions of developers around the world have used Twilio to unlock the magic of communications to improve any human experience. Twilio has democratized communications channels like voice, text, chat, video, and email by virtualizing the world’s communications infrastructure through APIs that are simple enough for any developer to use, yet robust enough to power the world’s most demanding applications. By making communications a part of every software developer’s toolkit, Twilio is enabling innovators across every industry — from emerging leaders to the world’s largest organizations — to reinvent how companies engage with their customers.

Source: Twilio Inc.

Media Contact:

Cris Paden

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