Connect with us

Hi, what are you looking for?


Cloud Security

Proofpoint to Acquire Tessian for AI-Powered Email Security Tech

Proofpoint removes a formidable competitor from the crowded email security market and adds technology to address risk from misdirected emails.

Securing Email

Enterprise security vendor Proofpoint on Monday announced plans to acquire email security specialists Tessian to beef up its ability to spot and block risky user behaviors, including misdirected email and data exfiltration.

Financial terms of the deal were not disclosed.

Tessian, a British startup that sells cloud email security software, was last valued at $500 million after its Series C funding round. The company raised approximately $128 million since launching in 2013 with ambitious plans to disrupt the email security market.

For the Thoma Bravo-owned Proofpoint, the deal removes a formidable startup competitor from the crowded email security marketplace and adds technology to address some of the most frequent forms of data loss, including misdirected email and data exfiltration

In a note announcing the transaction, Proofpoint pointed out that misdirected emails (sending emails to the wrong recipient) and mis-attached files are major causes of compliance violations and accidental data loss for organizations, noting that defenders are slow to detect and remediate a data loss and exfiltration incident caused by employee negligence.

Proofpoint vice president Darren Lee said the plan is to embed Tessian’s behavioral and dynamic detection platform into its own products to provide security tools that integrate natively with Microsoft 365 and Google Workspace.

The deal is seen as another sign of consolidation in an ultra-competitive email security category. Earlier this year, Cisco acquired Armorblox and venture capital investors place billion-dollar valuations on startups like Material Security and Abnormal Security.  

Other well-funded email security firms include Agari ($85 million raised), Valimail ($84 million raised), Area 1 ($82 million raised), Abnormal ($285 million), Avanan ($41 million), Inky ($32 million), and GreatHorn ($22 million). 

Advertisement. Scroll to continue reading.

Related: Analysis: The Race to Find Profits in Securing Email

Related: Email Security Vendors Score Billion-Dollar Valuations

Related: Thoma Bravo Buys Proofpoint in $12.3 Billion All-Cash Deal

Related: Email Security Firm Tessian Raises $65 Million at $500 Million Valuation

Written By

Ryan Naraine is Editor-at-Large at SecurityWeek and host of the popular Security Conversations podcast series. He is a security community engagement expert who has built programs at major global brands, including Intel Corp., Bishop Fox and GReAT. Ryan is a founding-director of the Security Tinkerers non-profit, an advisor to early-stage entrepreneurs, and a regular speaker at security conferences around the world.

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Join us as we delve into the transformative potential of AI, predictive ChatGPT-like tools and automation to detect and defend against cyberattacks.


As cybersecurity breaches and incidents escalate, the cyber insurance ecosystem is undergoing rapid and transformational change.


Expert Insights

Related Content

Application Security

Cycode, a startup that provides solutions for protecting software source code, emerged from stealth mode on Tuesday with $4.6 million in seed funding.

Cybersecurity Funding

SecurityWeek investigates how political/economic conditions will affect venture capital funding for cybersecurity firms during 2023.

Cyber Insurance

Cyberinsurance and protection firm Boxx Insurance raises $14.4 million in a Series B funding round led by Zurich Insurance.

CISO Conversations

SecurityWeek talks to Billy Spears, CISO at Teradata (a multi-cloud analytics provider), and Lea Kissner, CISO at cloud security firm Lacework.

Cybersecurity Funding

2022 Cybersecurity Year in Review: Top news headlines and trends that impacted the security ecosystem


The three primary drivers for cyber regulations are voter privacy, the economy, and national security – with the complication that the first is often...

Cybersecurity Funding

Network security provider Corsa Security last week announced that it has raised $10 million from Roadmap Capital. To date, the company has raised $50...


Thirty-five cybersecurity-related M&A deals were announced in February 2023