n. Non-personal, non-spam email messages that you have signed up for, but do not necessarily want or have time to read.
2011
In a world where BACN is the new SPAM, Unsubscribe.com is the new SPAM blocker.
2011
The smart labels feature essentially focuses on "bacn," that brand of e-mail that people subscribe to and generally want to read — but don't have time for right now. Think bank statements, neighborhood newsletters, airline frequent flier program updates and targeted advertisements from stores where you actually shop.
2007 (earliest)
Bacn is a new problem now plaguing our email inboxes. Putting it simply, Bacn is email you receive that isn’t spam… And isn’t personal mail. It’s the middle class of email. It’s notifications of a new post to your Facebook wall or a new follower on Twitter. It’s the Google alert for your name and the newsletter from your favorite company.
This word was coined in August 2007 at the Podcamp Pittsburgh 2 conference, as this video explains: