I recently spoke with someone who said his company had four billion email addresses, of which two billion had name and addresses associated. Considering the U.S. population was 313 million last time I checked, this really made me think about the industry and what we’ve become. I wrote an article a few months ago on the value of an email address: how it’s not only valuable as a monetization vehicle for communications, it’s essentially a primary key -- much like a mobile number and social security number for identifying an individual. The problem I have with four billion email addresses is that we’d have to assume each individual had over 10 email addresses. That’s not a reality, given 20% of the 313 million are under age 20 -- and from what the research has indicated, the “non-working” teens don’t use or prefer email as a primary channel. It’s not likely this group has seven to 10 managed email accounts, so does that mean the Boomer and Gen X generations carry the load? The challenge with having four billion email addresses is, in the end, accuracy. Which of these 10 addresses do you have on file with opt-in permission? This type of number is just mind-boggling from a marketer’s perspective, since - They think about a consumer as one email address and one physical address. - The ability to activate an email address after an early lifestage interaction is becoming more difficult, as a customer lifecycle is not linear in the digital world. - The ability to engage a customer through email across a portfolio of communications is becoming more costly and complex. - Over half the email addresses in a given database are dormant or relatively inactive. I wrote years ago on “The Generations” and how each used email. And if you apply how and why the different generations use email and match it to this mind-blowing number, the challenge seems too big to solve. When you add all this up, it tells you a couple of things. The email business will be around for a long time. If you aggregate across an industry, and were to see what types of email addresses engage with what type of activity, categories and interests and how many of those are the same person, it might change how you view a segment. When I hear 4 billion email addresses, I think of “engagement” combined with the term “audience.” It forces us to think more broadly and redefine how we view the influence of multiple channels.