Fun, fun–The rules to keep you from running afoul of the 2003 CAN-SPAM law continue to grow. Four new ones will go into force at the end of June 2008 and will apply to all “commercial” email campaigns, regardless of list size.

If you’re already trying to play by the rules, the rules do include one items many will be happy about. But one rule may cause big problems for affiliate marketing. Here’s the scoop based on a post CAN-SPAM New Rules Require Single-Option Opt Out by Christopher Knight over at Email Universe:

1. Recipients must be able to opt-out of a mailing with just a single action–either replying to the email, or clicking through to a single web page. No more clicking through to a page and having to get through several pages to completely unsubscribe. Or having to confirm your opt-out email you sent.

I also checked the FTC site and it says they can only require you to provide your email address and opt-in preferences. Personally, I’m thrilled with this rule–it should never be harder to unsubscribe than subscribe. If people don’t want to be on your list, they’re not good prospects for you anyway. As for making sure you’re in compliance with this, check with your email software provider, but most should already be doing single-action unsubscribes.

2. The FTC has also clarified that the you don’t have to be a company to be sending “commercial” email, that any individual or other entity who promotes a product, service or website in a message has to follow the rules as well.

3. Here’s what a lot of small businesses will like: you can now use a post office box or private mailbox (”PMB”) as the physical address in commercial mailings. It no longer has to be an actual street address for the company.

4. And here’s the potentially big problem for affiliate marketers: The new rule states that in a mailing with 3rd party advertisers, either the party who the email is “from” must have an advertisement in the email (in which case they become responsible for processing opt-out requests) or all of the advertisers with advertisements in the mailing are responsible for opt-out requests. This is known as the “Designated Sender” rule.

To me, newsletters are less of a concern because the sender nearly always includes some type of promotion for themselves. But affiliate emails–where one person emails their list just to promote someone else’s offer are more problematic because they don’t usually include other offers. So if it’s your program being promoted, you may now be responsible for making sure opt out requests from your affiliates’ email are processed in compliance with the law–although they’re not technically going to you.

I’ll poke around about this a little more and post what I find. Anyway, if you this law firm has a good summary of the CAN-SPAM law overall, with the new additions.