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The following excerpt is from Susan Gunelius’ book Ultimate Guide to Email Marketing for Business. Buy it now from Amazon | Barnes & Noble | iTunes | IndieBound

As an email marketer, you need to comply with laws that were put in place to protect consumers. While it might be tempting to buy a list of email addresses and just start sending messages to everyone on that list, this is a bad idea for a few reasons. First, you might be breaking the law. Second, you might be hurting your chances of your future email marketing messages getting into people’s email inboxes, including inboxes belonging to your own customers. The bottom line is, your actions as an email marketer can affect the deliverability of your email today and in the future.

The most important law you need to know and follow in the United States is the CAN- SPAM Act of 2003. This law applies to all forms of commercial email messages and not just commercial email messages sent in bulk to lists of people. What makes a message commercial? It’s not clearly defined in the Act, but it’s probably broader than you think. For example, a commercial message doesn’t have to promote a product or service directly to messages as be considered commercial. Even messages that promote content “any electronic on a commercial website—such as a blog post, free ebook, mail message, educational article, or tutorial—would be considered commercial since they indirectly promote the company.

The cost for non-compliance can be very high, particularly since you can be charged penalties for each separate email violation up to $40,654. Furthermore, if your email messages violate other laws, such as those related to deceptive advertising, you could face even more fines or criminal penalties, including imprisonment.

There are seven primary requirements of the CAN-SPAM Act. Following is a basic explanation of each of the main requirements. If you always err on the side of caution and assume messages sent from your company are commercial advertisements or promotions (even if they’re not directly advertising or promoting a product…