Startup Profile: Tessian

Tessian founders
  • Tessian is a British cybersecurity startup protecting businesses from email threats through its human layer security platform.
  • Tim Sadler, Ed Bishop and Tom Adams founded the company in 2012.
  • Tessian has raised a total of $59 million in funding from Sequoia Capital, Balderton Capital, LocalGlobe, Accel, Amadeus Capital.



About Tessian


Tessian’s three young founders, Tim Sadler, Ed Bishop and Tom Adams, were engineering graduates from Imperial College. They established in Tessian as the world’s first Human Layer Security platform on the premise that humans are the weak link in email and data security. Tessian’s mission is to secure all human-digital interactions within the enterprise and keep all sensitive data and systems private. 



Tessian’s founders Tom Adams, Head of Client-side Engineering, Tim Sadler CEO, and Ed Bishop CTO.



Tessian products use machine learning technology to protect email-users and prevent spear-phishing, accidental data loss, data exfiltration and other menacing email activity. The threat affects companies of all sizes with Hiscox, a large insurer, reporting that small businesses in the UK receive 65,000 targeted attacks every day. Those suffering from incidents face damages of around £25,000. 



How Does It Work?


Tessian protects businesses from insider and external email threats. There has been a continual rise in sophisticated cyber-attacks and, according to Verizon Data Breach investigation Report 2019, 96% of all social attacks occur over email. Human error is the root cause, as people are often not able to detect when cybercriminals impersonate colleagues, customers or suppliers in these targeted attacks. Tessian’s technology detects when an email represents a threat, reducing the chance of human error. 



Tessian cybersecurity
Tessian technology warns users against possible email threats.



The Tessian Defender uses machine learning to analyse past enterprise email data and uses this to differentiate between safe and threatening emails. It takes into account a range of data points from each email, such as headers, body text and attachments, to detect threats in real-time. This works to mitigate risk for enterprises against financial loss and reputational damage. 


The Tessian Defender consults a range of email data points to asses risk.



Tessian’s machine learning also evolves and improves itself over time and needs no configuring towards rules by system administrators. Administrators can instead investigate the activity flagged by the Tessian Defender and see detailed reports of past and present email security threats.



Tessian’s Success


Tessian now works to secure emails around the world, with offices in San Francisco and Headquarters in London. Tessian now has more than 150 employees, including 78 new hires in 2019 – a growth of 83%. 


Tessian Team
The Tessian team.


Tessian has seen rapid growth in the last few years. After a slower start, Tessian secured $2.7 million in its seed round in 2017. This was shortly followed by a $13 million funding round in 2018 and a further $42 million round in 2019. Tessian’s latest series was led by Sequoia.  


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