We've been protecting clients from cyber attacks for 15 years.

Our Team

J. Paul Haynes
Eldon Sprickerhoff
John Harris
Mark McArdle
Jamie Dool
Marko Obad
Mark Sangster
Dawn Leetham
Sean Blenkhorn
Bruce Johnson

J.Paul Haynes

Chief Executive Officer

J.Paul Haynes was drawn to eSentire with a vision to create a disruptive cybersecurity company that delivers what is now referred to as Managed Detection and Response (MDR). He successfully partnered with growth capital firms to invest in, and scale eSentire to become the world’s largest pure-play MDR provider and market leader. J.Paul is a professional engineer with a 25-year entrepreneurial track record of success. His business acumen, in-depth understanding of technology and strong leadership has made him a respected and reliable voice on the topic of cybersecurity in North America and Europe. He holds both a B.Sc. and M.Sc. in Engineering from the University of Guelph and is a proud alumni, currently serving on the Industrial Advisory Board for the University of Guelph’s School of Engineering and the Board of Innovation Guelph.

Eldon Sprickerhoff

Founder and Chief Security Strategist

Eldon Sprickerhoff is the original pioneer and inventor of what is now referred to as Managed Detection and Response (MDR). In founding eSentire, he responded to the incipient yet rapidly growing demand for a more proactive approach to preventing and investigating information security breaches. Now with over twenty years of tactical experience, Eldon is acknowledged as a subject matter expert in information security analysis. Eldon holds a Bachelor of Mathematics, Computer Science degree from the University of Waterloo.

John Hartley Harris

Chief Revenue Officer

As Chief Revenue Officer at eSentire, John leads the revenue teams (Sales & Marketing) and drives the company’s growth and market expansion. Through his 20 years of leadership-level experience, John has led companies through the full spectrum of growth internationally, including business combinations and IPO. He is a proven business builder of early stage, high-growth companies, influencing growth from start-up through to enterprise value (in the billions). Prior to eSentire, John proudly contributed leadership to Descartes (DSG:NASDAQ-1998, TSX-1997), ThoughtCorp (acquired by EPAM:NYSE) and RIS (acquired by Sierra:Private). He is a founding partner of New Carbon Economy Fund and JHH Holdings. John holds an Honours degree from the Ivey Business School at the University of Western Ontario where he played Mustangs Varsity hockey. He is the proud father to three children.

Mark McArdle

Chief Technology Officer

Mark McArdle is a seasoned technology executive with over 20 years experience with top technology brands, such as PGP Inc. and most recently McAfee's Senior VP for its consumer product development division. Mark defines new, leading edge products for eSentire and himself holds six patents in Internet security. Mark holds a Bachelor of Science degree from the University of Waterloo and completed the Ivey Executive Program in 2005.

Jamie Dool

Vice President, Engineering

As Vice President of Engineering, Jamie is responsible for leading eSentire's product development and quality assurance organizations and all aspects of system and service design, implementation and testing. Jamie is an experienced senior leader with a proven track record in the security software industry with companies like Magnet Forensics and McAfee, where he has led a variety of product development teams across enterprise, consumer, law-enforcement and government customers. He is named on several security patents and has a passion for technology that solves complex problems and customer driven innovation.

Marko Obad

Vice President, Systems and Infrastructure

As Vice President of Systems and Infrastructure at eSentire, Marko leads the company’s internal and customer-facing IT operations and customer infrastructure teams. With nearly 20 years of industry experience, Marko’s relentless dedication to project efficacy and efficiency is evident through a proven track record of enhanced offerings and seamless service delivery.

Mark Sangster

Vice President, Strategic Marketing

As a member of the LegalSec Council with the International Legal Technology Association (ILTA), Mark is a cybersecurity evangelist who has spent significant time researching and speaking to peripheral factors influencing the way that legal firms integrate cybersecurity into their day-to-day operations. In addition to his passion for cybersecurity, Mark's 20-year sales and marketing career was established with industry giants like Intel Corporation, BlackBerry and Cisco Systems. Mark's experience unites a strong technical aptitude, and an intuitive understanding of regulatory agencies. During his time at BlackBerry, Mark worked on the first secure devices for government agencies and has continued to build mutually beneficial relationships with regulatory agencies in key sectors ever since. Mark holds a Bachelor in Psychology degree from the University of Western Ontario, and a Business Diploma from Humber College.

Dawn Leetham

Vice President, Customer Success and Services

A talented project manager, Dawn Leetham brings over 20 years of combined project management and software solutions experience to eSentire. As the Vice President of Customer Success and Services, she specializes in ensuring that client needs are met with the right solutions and each project receives meticulous attention to detail. Dawn holds a Bachelor of Applied Science in Chemical Engineering from the University of Waterloo, and has been a Certified Project Management Professional (PMP) since 2005.

Sean Blenkhorn

Vice President, Solutions Engineering & Advisory Services

As a seasoned security leader, Sean Blenkhorn has spent much of his nearly 20-year career consulting with leading global (FORTUNE 50, 100, 500 and 1000) companies around security and compliance solutions. In his role as Vice President of Solutions Engineering & Advisory Services at eSentire, Sean leads his team globally as they provide guidance, consultation, and technical perspective to new customers as they evaluate and adopt eSentire’s award winning services to address their security and compliance requirements. Sean has an Associate’s Degree in Software Engineering from Georgian College.

Bruce Johnson

Sr. Director, Channel Sales

Bruce Johnson is a sales and operations executive with over 25 years’ experience in technology channels. A seasoned leader, Bruce is committed to building and scaling strategic leverage into sales models. As channel leader at eSentire, Bruce is responsible for the strategy and development of partner ecosystems and programs. Prior to joining eSentire, Bruce led channel sales and operations teams at Dell SecureWorks, SYNNEX and Symantec Corporation. He and his family live in Greenville, South Carolina.

Our History


Highly Commended as "Best Risk Management Technology Provider" at the HFM Services Awards

Received $11M Series 'B' Funding


Received $1M Series 'A' Funding


Managed Security Service Launched


eSentire founded

Our Affiliations


Financial Services Information Sharing and Analysis Center

Launched in 1999, FS-ISAC was established by the financial services sector in response to 1998's Presidential Directive 63. That directive - later updated by 2003's Homeland Security Presidential Directive 7 - mandated that the public and private sectors share information about physical and cybersecurity threats and vulnerabilities to help protect the U.S. critical infrastructure.

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Common Weakness Enumeration

Annual report International in scope and free for public use, CWE provides a unified, measurable set of software weaknesses that is enabling more effective discussion, description, selection, and use of software security tools and services that can find these weaknesses in source code and operational systems as well as better understanding and management of software weaknesses related to architecture and design.

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Software Assurance
Department of Homeland Security

The Software Assurance Program of the Department of Homeland Security's National Cybersecurity Division co-sponsors SwA Forums semi-annually with organizations in the Department of Defense and the National Institute for Standards and Technology.

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Hedge Fund Marketing Alliance

Since 2001, the Hedge Fund Marketing Alliance was designed for hedge fund professionals, financial advisors, investment consultants, and other professionals who are involved in the placement or distribution of hedge funds.

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High Tech Crime Investigation Association

The High Technology Crime Investigation Association (HTCIA) provides education and collaboration to our global members for the prevention and investigation of high tech crimes.

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Canada's premier IT Security Education Conference

SecTor is Canada's premier IT Security Education Conference. The annual event where IT professionals from throughout Canada can learn from and network with the world's most innovative, intellectual, exciting and entertaining security professionals. SecTor is IT Security Training at its best.

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Toronto Area Security Klatch

The Toronto Area Security Klatch (TASK) is an informal get-together of Information Security professionals (and those who want to be professional) that is held monthly in the Greater Toronto area. Our mandate is simple: to encourage discussion and share expertise in understanding the latest trends and security threats facing computer networks, systems and data.

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Organization for the Advancement of Structured Information Standards

OASIS is a non-profit consortium that drives the development, convergence and adoption of open standards for the global information society.

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