2.0 P3P Contact Purpose
P3P defines the Contact purpose as "Information may be used to contact the individual, through a communications channel other than voice telephone, for the promotion of a product or service. This includes notifying visitors about updates to the Web site. This does not include a direct reply to a question or comment or customer service for a single transaction."

The first thing you note is that just because you send an email, that doesn't mean you would have to declare this as a P3P purpose applicable to your site. A lot of times you will just be notifying a customer that a product has been shipped, their credit card was charged, answering a question they post to your site, or something just as innocuous.

The primary questions to ask when you are sending an email to a customer are:
   Is it a solicitation for a product or service
   Is it a sales message for a product or service
   Is it an advertisement for a product or service

If you can answer "yes" to any one of these questions then you are contacting for the promotion of a product or service (and remember, just because you are not selling it doesn't mean it is not a product or service). If it is just a customer service email then it won't fall under this P3P purpose.

2.1 P3P Policy Implications
When the "Contact" purpose is combined with a policy that collects Personally Identifiable Information then the agent evaluates delivery of cookies to the client. To have any effect of course, you have to be delivering cookies (the browser determines this by looking at the page header) to the client, and you have to have a privacy policy (for IE6 you must have a compact policy). If you are following good privacy practices then there will most likely be no effect on the cookies.

When these two elements are combined in the same policy, cookies will be "unsatisfactory" if the policy does not show you allow the user an opt-out or opt-in for the contact purpose element. It is beyond the scope of this article to discuss every setting of IE6 with regards to what will happen to cookies so we will just say that cookies can be denied or downgraded.

2.2 Clear Gifs In Emails
Clear Gifs are also known as Web Bugs and are used to track users on a web site, but they can also be used to track emails.

When a site uses HTML-based emails, they can use a Gif to let them know which emails have been opened by the recipients. This allows the site to gauge the effectiveness of the email program and the effectiveness of marketing campaigns.

If a site uses Clear Gifs in emails then there are P3P implications. First, the site must have user contact information since that is how they are using the email system (it really doesn't matter how the email addresses were obtained). Next, the purpose of the data collection will be "Individual Analysis" and/or "Individual Decision." The reason that it will be these purpose elements is because when the email is opened, the information can be tied to the email address which is individual contact information.