Logging in to unsubscribe

I have been talking with a company about their unsubscribe process and their placement of all email preferences behind an account login. In the process, I found a number of extremely useful links about the requirements.
The short version is: under the 2008 FTC rulemaking senders cannot require any information other than an email address and an email preference to opt-out of mail. That means senders can’t charge a fee, they can’t ask for personal information and they can’t require a password or a login to unsubscribe.
I’ve talked about requiring a login to unsubscribe in the past here on the Word to the Wise blog.
Let them go
Questions about CAN SPAM
One click, two click, red click, blue click
How not to handle unsubscribes
I’m not the only person, though, that’s written about this.
The FTC has written about it in the FTC CAN SPAM Compliance Guide for business

You can’t charge a fee, require the recipient to give you any personally identifying information beyond an email address, or make the recipient take any step other than sending a reply email or visiting a single page on an Internet website as a condition for honoring an opt-out request.

Al Iverson at Exacttarget has written about it in his blog post Require a login to opt-out

Senders are not allowed to require recipients to “provide any information other than the recipient’s electronic mail address and opt-out preferences.” That means you can’t require them to login to your website before continuing on to a preference center or other page. The only thing a recipient has to give you is their email address, and the opt-out preference. (i.e. do you want to opt-out from all messages, or would you like to opt-out only from certain specific lists.)

Even the forums at Y combinator have mentioned it.

It is definitely illegal to require a login. CAN-SPAM has many (many) faults, but it is extremely explicit about there being no funny business in the unsubscribe process.
Current FTC rules say that your unsubscribe link must either immediately unsubscribe the user or lead to a page that (at most) asks for only your email address and does not try to confuse or dissuade you.

The underlying goal of the rules is to give recipients the ability to make email stop. Requiring a password is one of the things bad senders do to add friction to the process. Because of the abuse of the login process, and the fact that sometimes the recipient doesn’t have the password (and can’t recover it) the FTC has decided no passwords for an opt-out.
This company is also a good example of how COI doesn’t fix everything. All registrations are fully confirmed. Yet, they still can’t manage to stop sending mail to people who didn’t ask for it or want it.
I’m pretty sure the company that triggered this discussion didn’t mean to violate CAN SPAM. But they did. I also expect that this may be the first time anyone pointed out the problem to them.