Dave Merkel

Co-founder and Chief Executive Officer Expel

Last Reviewed: September 26, 2026

Executive Summary

Dave Merkel is co-founder and Chief Executive Officer of Expel, a managed detection and response company based in McLean, Virginia, which he co-founded in 2016. Expel runs 24x7 security operations for its customers through its Workbench platform. Merkel came to Expel after roughly a decade building security products and services, most visibly as Chief Technology Officer and vice president of products at Mandiant and then as global CTO of FireEye after it acquired Mandiant. Before that he spent about ten years as a security practitioner: first as a special agent in the Air Force Office of Special Investigations, then as head of AOL’s technical security organization.

Career Highlights

• Co-founded Expel in 2016. SEC Form D filings name him an executive officer and director from the company’s first 2016 offering through its November 2022 filing, which lists him as Director and CEO.
• Global Chief Technology Officer of FireEye following its acquisition of Mandiant.
• Chief Technology Officer and vice president of products at Mandiant.
• Headed AOL’s technical security organization, where he created and ran the first incident response capability for AOL and Time Warner.
• Began as a special agent in the Air Force Office of Special Investigations, pursuing cyber criminals and conducting digital forensic investigations.
• Named to Washingtonian’s list of DC “Tech Titans”, including the 2026 list.

Professional Journey

Merkel started in information security as a special agent in the Air Force Office of Special Investigations. There he pursued cyber criminals and carried out digital forensic investigations; Expel’s own biography puts this “in the era of floppy disks and 2400 baud modems”. He moved to AOL as head of its technical security organization. At AOL he created and ran the first incident response capability for AOL and Time Warner, managed software security and policy programmes, and built technology for AOL’s security infrastructure.

He then spent about ten years on the vendor side. At Mandiant, the incident response and threat intelligence firm, he was Chief Technology Officer and vice president of products. When FireEye acquired Mandiant, he became FireEye’s global CTO.

In 2016 he co-founded Expel. Expel, Inc. was incorporated in Delaware that year and made its first sale of securities on 30 August 2016, a $7.5 million offering. The Form D for that offering names three executive officers and directors: Merkel, Yanek Korff and Justin Bajko. Bajko, who ran FireEye’s managed service delivery before Expel, is co-founder and Chief Strategy Officer, and Korff is Chief Operating Officer. The company’s most recent Form D, filed in November 2022 for a $30 million offering, lists Merkel as Director and CEO.

Expel provides managed detection and response (MDR). It monitors customers’ cloud, endpoint, identity, email, network and SaaS environments around the clock and responds to threats. It gives customers visibility into its analysts’ work through its Workbench platform. Its press releases include MDR coverage for Oracle Cloud Infrastructure, announced in March 2025. Other releases cover a managed SIEM service for Microsoft Sentinel and Splunk customers and agentic AI capabilities under its Ruxie AI brand.

Merkel is a regular commentator on security news. Washingtonian included him in its 2026 Tech Titans list of the Washington region’s technology leaders, and Expel says he has appeared on that list several times since 2015.

Education

No education details were found in any first-party source.