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Sending
What is Bulk sender?
In Gmail's and Yahoo's rules, a sender of about 5,000 or more messages a day to their users.
How it works in practice
Bulk senders must authenticate with SPF, DKIM and DMARC, support one-click unsubscribe on marketing mail and keep complaint rates low. Outlook.com applies similar authentication requirements. The counting is per domain, and once you're a bulk sender, you stay one.
The common mistake
Assuming the rules don't apply below the threshold. Unauthenticated mail is filtered or rejected regardless.
Check it yourself
Related terms
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