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About Callsign

How it all started

Our Mission

Callsign was founded in 2012 with the mission to provide the most secure and seamless authentication experience for enterprises and users.

Callsign’s Intelligence Driven Authentication Solution enables more informed and truly adaptive access control decisions, putting enterprises and their users back in control.

Today Callsign is deployed to hundreds of thousands of users globally. Our clients are enterprises, financial institutions and consumer-facing digital services and include some of the world’s largest banks, such as Lloyds Bank and Deutsche Bank.

Our investors

In July 2017, Callsign raised $35 million in Series A investment co-led by global venture capital firm Accel and PTB Ventures. Others who participated in the round include, Allegis Capital and NightDragon Security.

With this latest investment, Callsign will expand across the US and Far East, with plans to open offices in both the Bay Area and New York City this year.

Accel Logo
PTB Ventures Logo
Allegis Logo

Meet our board

Callsign’s board of directors draws on several decades of experience across the technology and cybersecurity sectors.

Chairman & CEO, Callsign
Zia Hayat

Zia is Chairman, CEO and founder of Callsign. With a PhD in Information Systems Security from the University of Southampton, he has served in various roles in the cybersecurity industry. From research engineer at BAE Systems to internet banking security architect at Lloyds Bank. Zia oversees the overall direction and strategy of the company while contributing to innovation and design of the service.

Vice Chairman, Callsign
Dave DeWalt

As the former CEO of FireEye, McAfee and Documentum, Dave has over 25 years of experience in the cybersecurity sector. He currently holds a number of board positions at leading cybersecurity firms, including Vice Chairman of ForgeRock and Vice Chairman of ForeScout Technologies, amongst others.

Accel Partners
Harry Nelis

Harry joined Accel Partners in 2004. As Partner, he invests in early and late-stage Internet and software companies. He is on the board of directors for a number of top firms, including KAYAK, Gameforge, CHECK24, and Before founding the venture-backed software company E-motion, Harry started his career as an engineer at Hewlett-Packard.

Allegis Capital
Bob Ackerman

Bob founded Allegis Capital in 1996 after a successful career as a serial entrepreneur. Bob is currently managing director of Allegis Capital and executive chairman of Founders Equity Partners. He also serves on the board of directors for RedOwl Analytics, E8 Security, CyberGRX and The DataTribe. Before moving into venture capital, he was the President and CEO of UniSoft Systems, a global leading UNIX Systems House and the Founder and Chairman of InfoGear Technology Corporation.

PTB Ventures
David Fields

David Fields is a founder and managing partner of PTB Ventures, a venture capital firm investing in early-stage companies in the digital identity ecosystem. David is a former private equity investment professional and brings over a decade of private investment and advisory experience both to his investors and his portfolio companies at PTB. He began his career as a credit analyst at Citigroup Global Markets and later served on the investment team at Cooper Investment Partners. David graduated from the University of Chicago with a B.A. in Economics and holds the Chartered Financial Analyst (CFA) designation.

Callsign in the News

Read news stories featured in publications around the world.