Quick facts
  • What we do:
    Machine Intelligent Email Security
  • Website:
  • Contact
    • Tessian Limited, Floor 3, 3 Finsbury Avenue, London, EC2M 2PA
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About Tessian Limited

Tessian offer a machine intelligent email security platform that keeps the world’s most sensitive data and systems private and secure, working with leading enterprises in finance, law and technology.

The company was formerly known as CheckRecipient to solve the problem of highly sensitive emails being sent to the wrong people. Co-founders Tim Sadler, Ed Bishop and Tom Adams saw an opportunity to disrupt rule-based email security by applying machine learning to large datasets, thereby preventing email security threats without the need for any predefined rules or end-user behaviour change.

Their highly skilled team of mathematicians, engineers and data scientists is dedicated to building next-generation technology and making the impossible possible every single day. They have enjoyed considerable success in this, raising more than $17 million from the world’s leading venture capital firms.

Tessian continues to maintain focus on their core values - boldness, passion and integrity - all in service of helping staff to achieve excellence and deliver success for clients.

What is it like to work for Tessian Limited

Tessian’s senior management frequently go above and beyond to challenge actions inconsistent with their values, including on key issues such as diversity. Efforts are also made to keep staff in the loop about key issues and priorities through regular daily updates.
Personal Growth
Personal Growth
Information security and data protection training is provided annually for all staff, as well as additional training as and when required. The company also offers role-specific training, which is dependent on the type of data accessed for the proper performance of the role.
My Company
My Company
When new staff are brought onboard, they are given a copy of Tessian’s company values in a booklet, with these founding principles also featuring prominently on their internal intranet. The firm also recently introduced a Donut App, pairing staff up with colleagues that they do not speak to often to meet for coffee.

Learn more about the 8 factors of workplace engagement here


  • Gym

    Companies offering either free gym/ sports facilities or offering subsidised gym membership for all employees

  • Maternity

    At least 10 weeks’ full pay or generous alternative

Company Statistics

  • UK sites:


  • Staff Turnover:


  • Average Age:


  • Staff:


  • Earning £35,000+:


  • Male : Female:

    76% / 24%

Regional Engagement

In the press


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