If you use webmail (e.g. gmail) you can mark it as spam and it'll ding their score. If they're using mailchimp et al you can report the spam to them though you

If you use webmail (e.g. gmail) you can mark it as spam and it'll ding their score. If they're using mailchimp et al you can report the spam to them though you might have to dig through their site to find the report address.