The FCC recently updated its rules regarding Voice Service Providers (VSPs) under the STIR/SHAKEN framework, which may affect Twilio customers handling outbound calls in the US. The new rules require businesses that originate calls on behalf of others or control phone numbers to obtain their own SPC token and STIR/SHAKEN certificate, sign their outbound calls, and assign attestation levels. Twilio recommends its customers consult legal counsel to determine if they qualify as a VSP under the new definition and what obligations that may entail. For affected customers, Twilio offers features such as Elastic SIP Trunking's PASSPorT Pass-Through feature and an upcoming Bring Your Own Token (BYOT) feature to support compliance with the updated rules.