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Trimarc: From Trimarcisia, “feat of three horsemen,” was an ancient Celtic military cavalry tactic where there was always a rider ready to mount the horse of a fallen soldier.

Trimarc was named based on this approach - even if the initial mitigation fails, there are additional defensive layers to back that up.

Trimarc is a professional services company based out of Washington, DC that helps organizations secure their Microsoft platform, both on-premises and in the cloud. Founded by Sean Metcalf, a Microsoft Certified Master in Active Directory, Trimarc's mission is to help organizations better secure their critical IT infrastructure.

We focus on a “reality-based security model” which targets attacker tactics and how to best stop them. Our methodology identifies security issues in an organization attackers could exploit to fully compromise the environment and provide custom recommendations to effectively mitigate these issues.

Trimarc works on continuously developing defensive strategies to combat evolving attack techniques. We focus on defensive layers within the enterprise – while any single defense may fail, there are others that compensate for this and provide additional detection and/or mitigation for that area.

Our "sales calls" don't include marketing slides or slick sales pitches; we just want to hear about your concerns and challenges. If what we do aligns with what you need, we can talk about scoping and next steps!

In the press

Trimarc in the Press


Strategies for securing identities in Azure Active Directory with Sean Metcalf


Cloud Backup and Cloud Storage Guide


6 vulnerabilities Microsoft hasn’t patched (or can’t)


CISA Launches JCDC, the Joint Cyber Defense


Black Hat: New CISA Head Woos Crowd With Public-Private Task Force


Reproducing the Microsoft Exchange Proxylogon Exploit Chain



Top 7 Hybrid Active Directory Security Sessions You Must Attend at Microsoft Ignite


Hybrid cloud complexity, rush to adopt pose security risks, expert says



How Cybercriminals Break into the Microsoft Cloud




Exploring, Exploiting Active Directory Admin Flaws







Advanced Techniques Attackers Use to Crack Passwords





Respect: Windows 10 security impresses hackers


Windows PowerShell 5.0 Expected To Add Improved Security


Improved Security Coming to Windows PowerShell 5.0


22 tips for preventing ransomware attacks


IT not doing enough to secure Active Directory, says expert

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