Cyberthreat investments soar along with attacks

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The more we hear about massive cyberattacks compromising the networks of multinational corporations, the more money venture investors are throwing at start-ups looking for a fix.

In the first half of this year, cybersecurity start-ups raised $1.2 billion, according to CB Insights. That follows $2.5 billion of investments in 2014, a 47 percent increase over the prior year.

Tanium and Illumio raised big rounds in the second quarter with technology designed to deal with the increased sophistication of modern-day hackers. Lookout raised $150 million to move from a consumer mobile security company to a business that can serve the biggest enterprises.

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Zscaler is the latest to join the mix. The San Jose, California-based company said Monday that it raised $100 million from TPG along with existing investors EMC and Lightspeed Ventures.

Founded in 2008, Zscaler develops software that inspects websites to make sure the bad stuff doesn't crack the walls, effectively blocking malware and cyberattacks. Businesses subscribe to the software-as-a-service (SaaS) platform and then direct their web traffic through Zscaler's system so that it can be thoroughly vetted.

It's a problem that plenty of companies have been trying to solve. Raytheon's Websense unit, Blue Coat Systems and OpenDNS all offer competitive threat detection suites.

"We have spent significant time looking at the cybersecurity space over the past few years, including much larger competitors to Zscaler," Nehal Raj, a partner at TPG, wrote in an email. "Unlike the appliance-focused incumbents, Zscaler's SaaS platform allows for massive scalability, facilitates adoption of a broad suite of solutions, and follows the overall migration of enterprise software to the cloud."

Zscaler's customer list of more than 5,000 companies includes Humana, Autodesk and Del Monte.