Halcyon
Halcyon is a cybersecurity company founded in 2021, specializing in anti-ransomware solutions. It has developed the industry's first dedicated anti-ransomware platform that utilizes AI micro-models and behavioral analysis to detect ransomware early, block attacks, and enable rapid recovery without the need for ransom payments. The company is headquartered in San Diego, CA, and operates with a fully remote workforce. Halcyon's platform offers a comprehensive suite of capabilities, including pre-execution defense, automated encryption key capture, and autonomous decryption. These features are d
Investing activity
Halcyon appears in 1 AI deal tracked by the AI Lounge deals desk. The rounds are mostly Seed, with a median round size of $6M. The most recent is Theorem (Seed, $6M, Jan 2026).
Halcyon most often invests alongside Khosla Ventures, Safe AI Fund, E14 Fund and Blake Borgeson, and the companies it backs on AI Lounge are mostly in AI.
Deals
Frequently asked questions about Halcyon
What AI companies has Halcyon invested in?
Halcyon's AI investments include Theorem. The 1 round on AI Lounge are listed on this page with amounts, dates and co-investors.
Where is Halcyon based?
Halcyon is based in San Diego, California, United States.
What stage does Halcyon invest at?
In the rounds tracked on AI Lounge, Halcyon has invested at Seed, with a median round of $6M.
Who does Halcyon co-invest with?
Halcyon's most frequent co-investors on AI Lounge are Khosla Ventures (1 deal), Safe AI Fund (1 deal), E14 Fund (1 deal), Blake Borgeson (1 deal) and Y Combinator (1 deal).
How can founders reach Halcyon?
Founders on AI Lounge can see Halcyon's contact details in AI Investor Contacts (paid plans), check for a warm introduction through members who worked with the firm under Warm Paths, and add Halcyon to their Investor Pipeline to track the conversation.