Job seekers and those with medically needy relatives are among those who cannot tolerate any false positive especially if calls are entirely rejected and cannot even leave a voicemail.

TMobile has 2 levels of it. One just labels the Caller ID for those suspected numbers as "Scam Likely". An additional feature (which OP is referring to) blocks the calls automatically.

I hope it works... it's kinda terrifying that getting no scam calls for 2 days is significant!

I have a test/dev phone that I used for a project several years ago with an associated ph#. I forgot about it (don't think about the charges accrued 8^) for several years, but just charged it and turned it on.

It's a number that was never used or answered for 3 years and it gets several scam calls a day. They must be calling every valid number.

I didn't realize they had added the block feature too, nice! Just went and enabled that

Does this work for the sweepstakes type scams where they try to induce the elderly send money for a fabulous prize they supposedly won? Just curious in general how they ID a scam?

The simplest and most powerful definition of "spam" is "whatever our users report as spam."

People don't mark calls as spam so I wonder how they do the training?

I believe Google recently released something similar for Android.

These calls are spam for phones. Certainly, there's an obvious pattern that can be identified and then neutralized.

Email spam became tractable on the end user side with domain and IP address risk scoring. Caller IDs are so easily spoofable it's like open relay email servers of the past.

When they spoof are they using otherwise valid numbers? That is, if you returned the call you'd speak to someone's grandmother?

None the less, can't the phone providers detect the excessive outgoing traffic? And if it's a residential number can't that raise a red flag?

Do you have a link for that? I have an Android phone, but I received a call marked as spam yesterday. I'd love to be able to just block those.