| Founded | 2013 |
|---|---|
| Closed | 2023 |
| Country | UK |
| Sector | Cybersecurity |
| Collapse type | Acqui-hire |
Tessian
"British AI email security startup that raised 130 million dollars and sold to Proofpoint for a fraction of its peak value as Microsoft built competing features natively."
Key Events Timeline
Tessian raised $130M from Sequoia and others to build an AI-powered email security platform that detected human errors, data exfiltration, and phishing beyond what rule-based systems could catch.
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