Neither SNS nor Twilio support arbitrary Sender ID's for US destinations, that's why I was asking... I wasn't aware that anyone actually allowed this anymore. C

Neither SNS nor Twilio support arbitrary Sender ID's for US destinations, that's why I was asking... I wasn't aware that anyone actually allowed this anymore. Companies that used to allow sending fake messages without authorization, like Sakari and Beetexting, no longer do. CTIA even made a statement that "no carrier has been able to replicate" this kind of attack, according to a VICE article.