Oh yeah carriers regularly filter based on content. I've posted about it extensively on HN before. I only have line-of-sight into them doing this for SMS messages arriving from businesses i.e. via Twilio, Telgorithm, Bandwidth, etc. I don't know one way or the other whether they also do this for regular SMS messages but I imagine automated 10DLC are under more scrutiny than a regular SMS user.
The filtering is phrase and word based generally, but sometimes also seems to use an ML model. We were able to use our own ML analysis to figure out the exact words causing content blocking and which carriers in a lot of scenarios. But yeah, it's definitely a thing at every major carrier.
The filtering is phrase and word based generally, but sometimes also seems to use an ML model. We were able to use our own ML analysis to figure out the exact words causing content blocking and which carriers in a lot of scenarios. But yeah, it's definitely a thing at every major carrier.