Sublime Security
Category: AI in Cybersecurity
An AI-powered, open platform for email security that allows security teams to write, share, and deploy custom threat detections as code. Sublime Security was founded in 2020. The company is led by Joshua Kamdjou. Based in Washington, D.C., USA. Team size: 51-200. Total funding raised: $243.8M. Latest round: Series C, $150.0M, 2025-10, led by Georgian. Key investors include IVP, Citi Ventures, Index Ventures, Decibel Partners, Slow Ventures.
- Founded
- 2020
- Headquarters
- Washington, D.C., USA
- Team size
- 51-200
- Total funding
- $243.8M
Value proposition
To move beyond traditional 'black box' email security by providing an open, programmable platform that gives security teams unprecedented visibility and control to defend against modern email attacks like BEC and phishing.
Products and solutions
Sublime Platform: An open and free platform for detecting email attacks., Sublime Defend: AI-powered threat protection., Sublime Control: Provides visibility and control over the email environment., AI Agent: Autonomously improves threat protection and reduces detection timelines.
Unique value
Sublime's primary innovation is its 'detections-as-code' approach, which allows security teams to write their own detection rules using a universal language (Python). This transforms email security from a closed, vendor-controlled system into an open, programmable platform.
Target customer
Enterprises with sophisticated security teams (e.g., SOC analysts, threat hunters, security engineers) who need customizable and transparent email security solutions.
Industries served
Technology, Financial Services, Healthcare, Enterprises with mature security programs across various sectors
Technology advantage
The key advantage is the combination of a powerful, adaptive AI for broad threat detection with the flexibility of an open, programmable platform. This allows customers to create highly customized, transparent, and rapidly adaptable defenses specific to their organization's threats, reducing reliance on vendor timelines and capabilities.
How they differentiate
Sublime Security differentiates itself by offering an AI-powered, programmable email security platform. Unlike traditional 'black box' solutions, Sublime provides greater visibility and control, allowing security teams to create custom detection rules and adapt to new threats in real-time. Their recent launch of an AI agent that autonomously improves threat protection further sets them apart.
Main competitors
Abnormal Security, Proofpoint, Avanan
Key partnerships
Microsoft (available on Azure Marketplace), Amazon (available on AWS Marketplace), Google Workspace (API integration), Strategic investors include Index Ventures, Decibel Partners, and Citi Ventures.
Notable customers
Specific customer names are not publicly disclosed, which is common for security companies.
Major milestones
Secured $60M in a Series B funding round in December 2024, led by IVP., Raised $20M in a Series A funding round in April 2024, led by Index Ventures., Launched its AI-powered email security platform and a new AI agent for autonomous threat protection.
Growth metrics
While specific growth metrics are not public, the company has gained significant enterprise traction and customer momentum, leading to a rapid succession of funding rounds (Series A and B within the same year).
Market positioning
Sublime Security is positioned as an innovator in the email security market, targeting enterprises that require more advanced and customizable threat detection capabilities than what legacy systems offer. They focus on augmenting, rather than completely replacing, existing email security infrastructure, offering a flexible and powerful layer of defense.
Geographic focus
Primarily North America, with headquarters in Washington, D.C.
Patents and IP
Information on patents is not publicly available.
About Joshua Kamdjou
Founder & CEO at Sublime Security, previously Cyber Security Consultant at SpecterOps, and Cyber Security at United States Department of Defense.
Official website: https://sublime.security