I need to start making notes of what newsletters I unsubscribe to, because some of them just keep re-subscribing me after some weeks/months. Wouldn't mind a blacklist service for this...
Will add them to the good old /dev/null folder.
Here's a good example that I suspected did not comply... also, examples of an address that I personally never use for newsletters. These are all confirmations of unsubscribing. They just kept adding me to different newsletters. Now sending this sender straight to trash.