Murray S. Kucherawy writes:

On Wed, Jun 4, 2014 at 8:39 AM, Stephen J. Turnbull <stephen@xemacs.org> wrote:

...

If I understand you correctly, we actually already have the mechanics for this in place. Most sites like Yahoo! allow you to whitelist a sender.

"You" here is the individual Yahoo! user. The whitelists are per-user.

If that's the case, you still have the scaling problem of populating the whitelist. How would Yahoo! go about doing that, for example? They claim at least 30,000 such cases that ideally would land in that list automatically somehow.

It's not "the" whitelist, it's all the users' personal whitelists.

I don't know if Yahoo! offers such whitelist capability, or if they simply use some heuristic based on the users' contact list, or what.