Mimecast Strengthens Security Leadership with Appointment of Leslie Nielsen as Chief Information Security Officer. Mimecast, a global cybersecurity leader redefining how organizations secure human risk through precision-engineered AI, has announced the appointment of Leslie Nielsen as its new Chief Information Security Officer (CISO).
Nielsen, a veteran with over 25 years of experience in cybersecurity, joins Mimecast from Klaviyo, a high-growth marketing automation platform, where he served as Senior Vice President and CISO. At Klaviyo, he played a pivotal role in scaling the company to $1.3 billion in revenue while fortifying its defenses, leading its security function through IPO readiness, and positioning the company to meet the demanding requirements of the public markets.
“We sought out a leader who can see beyond the noise and hype to deliver an innovative security platform, and Leslie fit the bill perfectly,” said Marc van Zadelhoff, CEO of Mimecast. “I’m excited to welcome him to the Mimecast team and for the expertise he brings in scaling world-class security at a time where cyber defense is at its most critical. Leslie’s proven experience leading security teams will be invaluable to safeguarding our customers and hardening our resilience strategy.”
In his new role as CISO, Nielsen will spearhead Mimecast’s global cybersecurity strategy, overseeing threat intelligence, risk assessment, incident response, and regulatory compliance. His leadership is expected to further reinforce Mimecast’s commitment to delivering the highest levels of protection for its more than 42,000 global customers.
Commenting on his appointment, Nielsen said, “I’m thrilled to join Mimecast on their mission to secure the human layer in the new age of AI-powered security threats. The industry is at a pivotal point where defense strategies must place humans at the center, and Mimecast has long been at the forefront of the human side of security. I look forward to building on the company’s strong foundation and helping shape its next chapter of innovation and resilience.”
Before Klaviyo, Nielsen held senior leadership positions at several leading technology companies, including SVP and CISO roles at Nuance Communications, SAP Concur, and SuccessFactors, as well as CTO at SOS Security. He also held senior positions at IBM and ACS (acquired by Xerox) and served as a member of Google’s CISO Cloud Advisory Board. He holds a Bachelor of Science degree in Computer Science from Texas Tech University.
With Nielsen at the helm of its security strategy, Mimecast strengthens its leadership team at a time when cybersecurity threats are becoming increasingly sophisticated, reinforcing its mission to protect organizations against the evolving risks of the digital era.