Halcyon
Track on RadarAnti-ransomware platform for detecting and preventing ransomware attacks
- Total raised
- $190M
- Employees
- 532
- Founded
- 2021
- Momentum
- 46
Cooling
Data updated August 2026
About
About Halcyon
At a glance
Halcyon is a cybersecurity company specializing in Endpoint Security, founded in 2021 and headquartered in Austin, United States. It has raised $190M in total funding, employs about 532 people, and is privately held.
Halcyon is a cybersecurity company founded in 2021 by veterans from Boldend, Cylance (Blackberry), Accuvant (Optiv), and ISS X-Force (IBM). The company specializes in anti-ransomware technology, building an enterprise platform designed to detect, prevent, and respond to ransomware attacks and advanced threats. The company's platform is purpose-built to address ransomware threats that evade traditional security tools, targeting mid-market and enterprise customers. Halcyon's approach combines detection capabilities with response mechanisms specifically engineered to counter ransomware operations. The company operates as a fully remote, globally distributed workforce headquartered in San Diego, California. The founding team includes CEO Jon Miller, who previously served as Chief Research Officer at Cylance and was an early employee at Accuvant, and CTO Ryan Smith, who has over 25 years of experience in vulnerability research, exploitation, and machine learning applications in security. Halcyon's technology focuses on preventing ransomware attacks from causing catastrophic organizational impact by addressing the limitations of modern security tools that may miss sophisticated ransomware variants. The platform serves organizations seeking dedicated protection against ransomware threats as part of their security infrastructure.
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FAQ
Frequently asked questions about Halcyon
When was Halcyon founded?▾
Halcyon was founded in 2021.
Where is Halcyon headquartered?▾
Halcyon is headquartered in Austin, United States.
How much funding has Halcyon raised?▾
Halcyon has raised a total of $190M in total funding.
Is Halcyon public or private?▾
Halcyon is a privately-held company.
How many employees does Halcyon have?▾
Halcyon has approximately 532 employees.
What does Halcyon do?▾
Halcyon is a cybersecurity company founded in 2021 by veterans from Boldend, Cylance (Blackberry), Accuvant (Optiv), and ISS X-Force (IBM). The company specializes in anti-ransomware technology, building an enterprise platform designed to detect, prevent, and respond to ransomware attacks and advanc…
