SMS Blocking by Carrier Policies

Anonyome Labs/MySudo does not inspect your messages while they pass through our service. However, once your SMS leaves our boundary and enters the public telecommunications network, delivery and inspection are out of our control. The only way to guarantee zero inspection is by messaging MySudo-to-MySudo, which is fully end-to-end encrypted (E2EE) and cannot be read or intercepted by anyone, including us.

Why SMS may be blocked
To protect recipients, the Cellular Telecommunications and Internet Association (CTIA) maintains a list of prohibited content for SMS messages, known as S.H.A.F.T.:

• Sex

• Hate

• Alcohol

• Firearms

• Tobacco

Other prohibited content is detailed in our Fair Usage Policy, including:

• Loan offers, credit repair, debt collection, high-risk financial services

• Pharmaceuticals, including cannabis and related paraphernalia

Recently, carriers have enforced stricter rules around S.H.A.F.T., and SMS containing profanity or certain keywords may be blocked by downstream carriers.

Tips to avoid SMS blocks

• Keep all communications Sudo-to-Sudo within MySudo to use E2EE. Messages sent this way cannot be inspected or blocked.

• Avoid profanity or S.H.A.F.T.-listed content in SMS messages.

• A minor workaround: slight misspellings or added characters can sometimes bypass keyword blocks (e.g., “wor#d”).

For reliable delivery and privacy, invite your contacts to MySudo and use encrypted messaging, calling, and email instead of standard SMS.