Then they will go into their email client and click the spam button on both of the emails that I sent them. The confirmation email, and also the test email.

Even though they requested these emails. Even though both emails have an unsubscribe header and link which takes them to a place where they can opt-out in perpetuity from receiving any further email from me.

I know this, because I get feedback loop emails when people do it.

This happens regularly.

They then told their email provider that the email they requested was spam.

I've considered putting up a page with a list of these peoples email addresses, but I feel like it would end up causing me more problems than it's worth.

[edit] There should be a system where I can prove to an email provider that I was in fact given permission to send to an address (for a period of time, and/or for a specific quantity of messages). If there was a standard email header where you could stick a callback URL like:

  Request-Permission: url=https://www.example.com/callback period=1D count=10

Once pressed, it would replace the “spam” UI element with “unsubscribe”.

Yes. It’s clear that you have no intention to reach them afterwards. But to them it is not so clear, and they mark these innocent letters as spam preventively, out of habit, cause other sites committed abuse in the past and they don’t want to test yet another service’s good nature. Much easier to ban you forever and forget about that, even before you did something unexpected. I know it’s unfair, and I don’t act like that, but they can and some of them do. No time on their hands to differentiate. Modern email culture is rotten to the core and popular email services only cultivate that.

It's worse because the next time you receive a post from a newsletter you unsubscribed from, which may be weeks after you unsubscribed, you may actually start doubting if you did unsubscribe from them. There's no way to know, and this seeds some doubt in your mind.

So the next time you want to unsubscribe from a newsletter, legit or not, you're just going to press the spam button because there's no downside to you as the reader, but there is the upside that your mail client will from now on keep out the newsletter posts no matter if the newsletter would actually have unsubscribed you or not. Basically the "mark as spam" button is a 100%-unsubscribe button, while the unsubscribe button is a 95%-unsubscribe button.

I don't believe the situation of malicious actors in newsletters is actually as bad as some HN comments make it appear. Most legit use double opt-in and have good unsubscribe policies. As usual it's the few bad ones that ruin it for everyone.

I wish I had a 95% success rate when trying to unsubscribe...

I've given up on unsubscribing the 'right' way. Too much bs most of the time. It's now just mark as spam and move on.

I'm not sorry if I threw anyone's metrics off, they broke the law, they spammed me, it's on them.

I think this is received wisdom that might have been true 20 years ago, but doesn’t stand up to scrutiny.

So for me, it does stand up to scrutiny, it still happens.

But I have scripts that count them, and when they get to five I then make the decision. Again, sometimes I continue simply to bin them, but sometimes I click the unsubscribe link. Mostly then they stop and there's no additional problem, but more than once that address has been used on other spam emails, and only after the unsubscribe.

Do you have actual evidence that it doesn't happen? You might, as others have, be arguing that it's not worth the spammers' effort. But setting up a script triggered by an unsubscribe is pretty trivial, and emails can then be sold at a premium, accompanied by a certificate of sorts that the address is valid.

So maybe it is worth their while.

I've noticed a few times that a company I have unsubscribed from years ago will suddenly start sending me mail again. Usually I'll just re-unsubscribe and they'll go away again.

I've also had it several times that I clicked on an Unsubscribe link and the resultant page indicated I had been removed from the list but I continued to receive mail noticeably past the date indicated ("it may take up to a week for your name to be removed, as some mail is queued in advance"). Conveniently, when I followed the link with my ad blocker disabled the request succeeded (without any change in appearance), but I actually stopped receiving their spam.

I can't say anything about email newsletters, because I don't subscribe to them.

You're assuming that they willingly signed up for it and weren't added to the list because of someone selling their data to another marketer, a dark UX pattern tricking them into signing up for the newsletter when they made a purchase, etc.

I tend to agree. Also, newsletter that try to track me with invisible pixels can go to hell, too.

Sometimes the spam/phishing line is hard to draw (especially without clicking a link and seeing what they try to make me do) and the 'unsubscribe' link is clearly just part of it, too.

Does anyone know what 'report phishing' actually does in Fastmail? I've had to use it a lot recently, and could easily create a rule for when I've been doing it, if only 'report phishing' was an available action. That it isn't makes me wonder if there's manual review or something so they don't want so much bulk? (And in that case probably also don't/want need my tens of ~duplicates a day.)

Yeah that's the better part of 95% of them for me.

100% of them for me because i don't want any stupid newsletters. Yes, all of them go into the spam folder.

For some business that I otherwise am a customer off i also forward their shit spam to their support and tell them to unsubscribe me, even if they have a link. For the simple reason that if they feel like they can waste my time with their shit, i'm gonna waste theirs too.

If you're running a legit newsletter that people want I can't imagine enough people would be marking it as spam for it to actually affect your reputation.