Omnivore, MailChimp's abuse-prevention initiative, keeps our system clean by gathering information from billions of emails and predicting bad behavior in campaigns before they even get out the door.

Omnivore is constantly at work in the background, analyzing email-campaign data and staying on top of evolving user behavior. If Omnivore detects a suspicious activity, we suspend the account while a team of people investigates—and if it's clear that an account is malicious, we shut it down.


Omnivore analyzes lists.

MailChimp's Email Genome Project scans billions of email addresses for information that can improve our deliverability and train Omnivore to recognize abuse. Our technology tests both negative results (like bounces and unsubscribes) and signs of engagement (like opens and clicks), showing us the big picture of any given campaign.

Omnivore reviews content.

We're even scanning the content of emails for bad URLs and questionable keywords. We use blacklists, stats we've gathered, and our own technology to predict whether or not particular email content is going to cause a problem.

Omnivore monitors user behavior.

We're constantly studying and recording user-behavior patterns. This allows us to run a large-scale scan for users who might be sending campaigns too quickly or obviously trying to stay below MailChimp limits.

Omnivore is getting smarter every day.

Thanks to Omnivore, we sent 50,000 warnings and shut down 45,905 malicious accounts in 2011 alone. Omnivore also teaches us valuable information that we can share with our subscribers, like the fact that a single opt-in list will have twice the amount of bounces as a double opt-in list.

Omnivore affects you.

Since our technology prevents abuse on such a massive scale, you'll achieve better deliverability by default — because even problem-free senders benefit from a self-cleaning system.

Omnivore exists not only to prevent abuse within MailChimp's system and maintain our reputation, but also to improve the email ecosystem as a whole. Because MailChimp cares about the ecosystem.