Leadership Team
GreatHorn was founded by security industry veterans with decades’ experience protecting organizations and solving complex cybersecurity challenges. Learn more about them below.
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Kevin O’Brien is GreatHorn’s CEO and Co-Founder. Under Kevin’s leadership, GreatHorn has become the world’s leading next-generation email security company, analyzing billions of messages and stopping phishing attacks that target a global customer base of organizations, both public and private.
Kevin brings deep industry experience, having been an early member of multiple successfully exited security companies, including CloudLock (Cisco), Conjur (CyberArk), and @stake (Symantec). Prior to founding GreatHorn, Kevin was Vice President of Marketing at Conjur, where he built the early go-to-market team responsible for initial market positioning and growth. Previously he led product marketing and sales engineering efforts at CloudLock, the leading cloud access security company that now has more than 6 million enterprise users.

Ray Wallace is GreatHorn’s Chief Technology Officer and Co-Founder. Ray is responsible for GreatHorn’s overall product strategy, development, and continuous innovation for its next-generation email security platform.
Ray brings more than a decade of experience building complex security and software systems and product platforms. He has deep domain experience in application and database security, front and back-end infrastructure and domain analytics.
Prior to GreatHorn, Ray held senior engineering roles at companies including Brainshark, Courion, and Application Security.
Ray studied computer science at Rochester Institute of Technology.

Jim is the Vice President of Engineering at GreatHorn. At GreatHorn, Jim manages the development of GreatHorn’s security products and cloud services as well as the incorporation of next generation machine learning and analytics capabilities into its products.
Prior to joining GreatHorn, Jim was the Vice President of Engineering at Akamai Technologies where he managed engineering for the mobile BU from its inception. While at Akamai, he focused on dramatically increasing the quality of experience for media, e-commerce, IoT, and fin-tech subscribers using mobile devices.
Prior to Akamai, Jim spent 25+ years building cutting-edge, high-speed networking equipment for carriers and enterprises at companies, such as Ericsson and Bay Networks/Nortel and a number of start-ups. In his career, Jim has authored 20+ patents and patent proposals and has been an active member of multiple standards bodies, including the IETF where he coauthored 10+ RFCs and internet drafts.
Jim received a Ph.D. in Computer Engineering from Syracuse University where his dissertation focused on analytical modeling of complex systems and networks. He also holds a BS in Computer Science from the Pennsylvania State University.

Michael Mayer is GreatHorn’s Vice President of Sales. Mike manages the lead development organization, Inside Sales, Field sales and the Channel for GreatHorn globally. He joins with over 20 years of sales and leadership experience. Mike has led global sales, marketing, and channel organizations for the fortune 500 and developed aggressive growth strategies for emerging technology and SaaS companies.
Mike started his career as an Inside Sales rep at Dell selling computers in the Consumer division. He had several roles in direct sales in SMB, Mid- Market and Large Enterprise before becoming a Sales Manager and eventually a Director for Dell managing multiple sites and divisions. He was a recipient of Dell’s prestigious Vice President’s award and a constant annual and quarterly sales award winner for both management and Direct Sales.
In 2009 Mike helped VMWare expand their Austin sales location and build out their Direct and Channel Inside Sales Division. From there, Mike joined the Channel Organization and managed the top revenue producing partner for VMware. Mike negotiated sensitive partner engagements between the two companies and played a major role in the partner being recognized as SMB partner of the year for VMware. Mike was a member of VMware Advanced Leadership Program before he left to start his own Global Channel organization for Peer1 Hosting.
Mike lead two organizations through major acquisitions. At Peer1, Mike grew the channel 400% in the course of year across Europe, North, and South America. His Channel program was recognized as a top partner program in CRN as Peer 1 continued to pull partner share from other major hosting companies. This growth eventually contributed to the Acquisition of PEER1 by Cogeco. From there Mike went to ASG Software and led their Inside Sales and Channel Organization through a bond acquisition by Several Private Equity firms. After the Acquisition Mike relocated to Boston to work for Akamai.
At Akamai, Mike led the Emerging Business Division which consisted of the Acquisition and Retention teams for the Americas. The organization consisted of 80 people across the US and Bangalore, India. It delivered record setting new customer numbers for the company and significant year over year growth. After Akamai, Mike served as a member of the Executive team at CNE Direct leading their sales and marketing division.
Outside of work, Mike serves as a contributing advisor to GLG and Alpha Sights, he is a coach for youth sports, and is an active volunteer for the North Shore YMCA, local schools, and other philanthropy groups.

Matt Petrosky is the Vice President of Customer Experience at GreatHorn. Matt is a versatile leader with 15+ years in technology organizations, designing products and customer experiences, most recently in the rapid growth cybersecurity industry.
After an honorable discharge from the United States Navy, Matt embarked on an impressive career building customer success and product management teams from the ground up. Prior to joining GreatHorn, Matt was Director of Product Management at Carbon Black. He began his 12-year endeavor at Carbon Black as a sales engineer evangelizing the company’s emergent technology to prospects, executing technical evaluations, and speaking at conferences. Matt went on to direct the successful implementation of Carbon Black’s software for strategic-named accounts, technical troubleshooting for customers and partners, and aligned both the internal and external community teams with Carbon Black’s strategic mission.
Matt received a Bachelor of Science in Industrial Management from Carnegie Mellon University, an MBA in entrepreneurship from Babson College, and is CISSP certified.

Ann Sharon is Vice President of Operations at GreatHorn. She is responsible for the operational aspects of GreatHorn’s processes and procedures, including the company’s go-to-market and compliance programs.
Ann is experienced in operations and program management, proficient in leading cross-functional programs and initiatives in early-stage start-ups, high growth, and mature companies.
Prior to joining GreatHorn, Ann served as Vice President of Business Operations for CloudLock (acquired by Cisco), where she helped drive the go-to-market strategy and lead many cross-functional programs. Prior to CloudLock, Ann managed the EMC Secure Remote Support portfolio overseeing product and program management.
Ann began her career in the IDF serving in the Air Force computer unit. She holds a high-tech MBA from Northeastern University and a BSc in Industrial Engineering from The Technion Institute of Technology.

Annie Wacker is GreatHorn’s Chief Marketing Officer. Annie is responsible for the global development and execution of GreatHorn’s brand awareness, demand generation, product marketing and analyst relations. She joins with over 20 years in the information technology industry, with a focus in cybersecurity. Annie is a “go to” global marketing leader in the industry, producing aggressive strategies to support revenue growth.
Annie has worked for private and public companies, both in the US and internationally. Annie brings a deep understanding and track record in B2B marketing, including brand awareness, product marketing, demand generation and marketing operations. Her ability to build high-performance teams and deliver impactful results makes her a tremendous asset to the organization. Her staple marketing rule is to never sacrifice quality for the sake of quantity.
Outside of work, Annie enjoys spending time with her family, philanthropic activities, and hiking.

Connie Yuen joined GreatHorn as the VP of Finance in September 2019. Connie has over 20 years of progressive experience in managing finance and accounting operations. She has played major roles in streamlining business processes, debt financing, and M&A activities. Most recently she was the Corporate Controller for Localytics. Prior to that she held senior financial roles with cybersecurity software companies, CloudLock (acquired by Cisco) and CounterTack.
Connie holds a business degree from UMass Boston and an MBA from University of Phoenix.