Valuation: $26.06 millionTotal raised to date: $46.16 millionYear founded: 2015HQ: New York
What it does: BigID offers a way for companies to find and identify their most sensitive data — helping its customers both meet privacy regulation requirements, while also giving a tool to assess the damages in the event of a breach.
Why it's hot: Data protection and privacy tools became even hotter Europe introduced its GDPR privacy regulations in May 2018. The resulting helped the company raise $30 million this year from investors like Scale Venture Partners and the investment arms of Comcast and SAP. BigID Founder and CEO Dimitri Sirota also sold his previous security startup to CA in 2013.
Valuation: $32 millionTotal raised to date: $9.6 millionYear founded: 2016HQ: Somerville, MA
What it does: Kolide is a cloud service that analyzes a company's Macs and PCs to find problems with devices — everything from security issues to repair needs — and suggests fixes.
Why it's hot: This startup was launched by the creators of a popular open source project called osquery developed inside Facebook. It helps protect Macs, Windows and Linux computers from hackers.
Valuation: $100 millionTotal raised to date: $32.04 millionYear founded: 2015HQ: London
What it does: Snyk automates the process of finding and fixing vulnerabilities in open source software. In other words, it will continuously keep finding and fixing security issues in the open source code that powers much of the world's underlying computing infrastructure.
Why it's hot: This year, Snyk raised $22 million at a $100 million valuation. With open source software only getting more popular with developers, Snyk might be on to a big market.
Valuation: $900 millionTotal raised to date: $223.3 millionYear founded: 2011HQ: Atlanta, GA
What it does: Prevents telephone fraud by using artificial intelligence to identify people's voices.
Why it's hot: This company is backed by numerous big names including Martin Casado at Andreessen Horowitz and former Cisco CEO John Chambers. In December it raised an additional $90 million to expand internationally. It boasts 8 large banks and 5 large insurance companies as customers, covering more than 200 million of their accounts, the company says.
Valuation: $925 millionTotal raised to date: $220.04 millionYear founded: 2011HQ: San Francisco
What it does: Fastly is an edge content delivery network, or CDN. It helps its customers speed up their websites and apps load — which has the pleasant side-effect of helping detect when inbound traffic is actually an attack of some kind, and warding it off.
Why it's hot: Fastly has come on strong in this well-established market, where it competes with fellow statup Cloudflare. Fastly already powers sites such as Airbnb, GitHub, Alaska Airlines, Pinterest, Vimeo, The Guardian, and the New York Times.
It reportedly broke the $100 million revenue mark in 2017, and in 2018, Fastly raised funding that included backing by the investment arm of telecom giant Deutsche Telekom.
Valuation: $1.18 billionTotal raised to date: $267.5 millionYear founded: 2013HQ: Sunnyvale, CA
What it does: Illumio helps customers monitor their applications for the tell-tale signs that they've been hijacked by hackers.
Why it's hot: Illumio fast growth propelled it to "unicorn" status — startups valued at $1 billion or more — just six months after it came out of stealth mode. In 2018, the company says still grew fast, increasing its bookings (a term for revenue under contract), by 300%, it said.
Valuation: $1.9 billionTotal raised to date: $174.53 millionYear founded: 2012HQ: San Francisco, CA
What it does: HashiCorp is an open source cloud infrastructure automation company. For these purposes, it means that it offers tools to help developers automatically maintain and secure their cloud computing infrastructure.
Why it's hot: HashiCorp started as a passion project, but it became so popular and widespread that the creators quit their day jobs to launch a business that's now valued at $1.9 billion after only six years. Developers all over the world rely on HashiCorp's tools to secure their clouds.