# Marshall Heilman

> Marshall Heilman is the Miami-based CEO of DTEX, a cybersecurity executive whose career runs from networking and information security in the U.S. Marine Corps through red-team and incident-response leadership at Mandiant to the executive suite. After 17 years helping Mandiant grow from a startup into a public company and Google acquisition, he joined DTEX in December 2023 to make insider-risk management earlier, more contextual and more attentive to human behavior. He also advises cybersecurity companies through Ballistic Ventures.

- **Role:** Chief Executive Officer at DTEX
- **Organizations:** DTEX, Ballistic Ventures, Google Cloud, Mandiant, FireEye, United States Marine Corps
- **Education:** BS, Computer and Information Science, University of Maryland Global Campus, MBA, W. P. Carey School of Business, Arizona State University
- **Known for:** Helped Mandiant grow from a startup into a public company and ultimately through its acquisition by Google., Held global leadership responsibility across Mandiant consulting, threat intelligence, incident response, red-team operations and managed defense., Grew Mandiant's managed detection and response offering during three years as its general manager.

## Career timeline

- **1998-2006** — Served in the United States Marine Corps, specializing in networking, communications and information security.
- **2006-2015** — Joined Mandiant and advanced to managing director, working in incident response and red-team operations.
- **2015-2017** — Led global incident-response and red-team operations as a Mandiant vice president and CTO for those practices.
- **2017-2021** — Served as executive vice president for Managed Defense and Advanced Practices at FireEye/Mandiant.
- **2021-2022** — Became Mandiant executive vice president and global chief technology officer.
- **2022-2023** — Continued as Global CTO for Mandiant after its acquisition by Google.
- **2023** — Appointed CEO of DTEX in December.
- **2024** — Joined Ballistic Ventures as a threat-intelligence advisor; DTEX raised a $50 million Series E led by CapitalG.
- **2026** — Advanced the view that enterprise AI agents should be treated as insiders and monitored through behavioral context.

## Achievements

- Helped Mandiant grow from a startup into a public company and ultimately through its acquisition by Google.
- Held global leadership responsibility across Mandiant consulting, threat intelligence, incident response, red-team operations and managed defense.
- Grew Mandiant's managed detection and response offering during three years as its general manager.
- Led DTEX through a $50 million Series E financing led by CapitalG in March 2024.
- Became a threat-intelligence advisor to Ballistic Ventures in 2024.
- Spoke at RSA Conference on intelligence-led security and has appeared in industry interviews on red teaming, incident response and insider risk.

## Latest updates

- **2026-09** — Argued that CISA insider-risk guidance should explicitly extend to AI agents.
- **2026-06** — Presented DTEX's approach to AI risk management for enterprises where people, copilots and autonomous agents share data and workflows.
- **2026-05** — Participated in an RSAC discussion on AI-agent security, governance and the need to understand how agents complete assigned tasks.
- **2026-02** — Commented on research estimating average annual insider-risk losses of $19.5 million and urged organizations to classify AI agents alongside human insiders.
- **2024-12** — DTEX established an advisory board with former intelligence officials Susan M. Gordon and Mike Studeman.
- **2024-03** — DTEX closed a $50 million Series E led by CapitalG, bringing announced total funding to $138 million.

## Links

- Website: https://www.dtex.ai
- LinkedIn: https://www.linkedin.com/in/marshall-heilman
- YouTube: https://www.youtube.com/watch?v=KXugD26sPRw

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Profile page: https://yespress.io/marshall-heilman
Published by YesPress — https://yespress.io
Last updated: 2026-09-28