Yahoo officially stated that:

“Beginning the week of June 3, 2013, older versions of Yahoo! Mail (including Yahoo! Mail Classic) will no longer be available. After that, you can access your Yahoo! Mail only if you upgrade to the new version. When you upgrade, you will be accepting our Communications Terms of Service and Privacy Policy. This includes the acceptance of automated content scanning and analyzing of your communications content.”

In last December, Yahoo launched the new Mail version and announced that they would discontinue the Mail Classic in April this year. Not until recently when Yahoo began sending emails to Classic Mail users about the migration to new Yahoo mail version, did Yahoo mentioned anything about the new terms of use and new privacy policy of the new Yahoo mail.

Now Yahoo requires all Mail users to switch to the new version of Mail and accept a TOS/Privacy Policy update that lets it scan emails to “deliver product features, relevant advertising, and abuse protection”. You can opt out of the ads, but if you don’t want to be scanned, you have to ditch Yahoo Mail.

Those who upgrade can opt out of contextual ads through Yahoo’s Ad Manager. Yahoo bluntly tells users who refuse its new policies that they should either download their mail to another IMAP client, or close their account. Premium Mail Plus users who want to cancel their accounts can get a prorated refund. Basically all free Yahoo email accounts will be forced to be scanned for their target ads. Looks like what Yahoo really eliminates is not the Classic Mail, but the free of use of their email service. Yahoo is following Google. Gmail has long scanned your email to show you related ads.