What is a Secure Email Gateway?
Many companies use extra layers of security on top of their regular email provider (ESP). These are called Secure Email Gateways (SEGs) — tools like Barracuda, Mimecast, Proofpoint, and Cisco - email firewalls.
They filter, block, or quarantine messages before they ever reach the recipient. Reaching these inboxes is far more difficult and often wastes time and hurts deliverability.
How Instantly Helps
Instantly will automatically flag contacts protected by SEGs as soon as you upload a list.
Live in your Leads table: SEG labels appear right away.
API support: You can enrich and detect SEGs programmatically.
Why It Matters
By identifying SEGs early, you can:
Avoid sending to hard-to-reach leads.
Protect your domain reputation and inbox placement.
Focus campaigns on contacts most likely to open and respond.