Act Security
Act Security is a cybersecurity company in Tel Aviv, Israel, founded in 2025. It has raised $60.0M across 2 rounds, most recently a $40.0M Series A in December 2025.
Cloud infrastructure and data center security
- Headquarters
- Tel Aviv
- Employees
- 11–50
- Founded
- 2025
- Business Model
- B2B
- Website
- act.security
- Total Funding
- $60.0M
- Last Round
- $40.0M Series ADec 2025
- Rounds
- 2
Totals include recorded grants and other qualifying funding, not just equity. What counts toward funding.
Indexed holds 2 funding rounds and 3 investors for this company. The full record is or through the API.
About
Act Security is an Israeli cybersecurity startup founded by the team behind Medigate, the medical device security company acquired by Claroty for approximately million in 2021. Act Security was co-founded by Jonathan Langer (CEO), Itay Kirshenbaum (CTO), Stephen Goldberg (Chief Product Officer), and Ilai Fallach (Chief R&D Officer), who collectively built and exited Medigate. The company develops a platform for securing cloud infrastructure and data centers, addressing the growing challenge of protecting modern hybrid environments. Act Security raised a million seed round in 2025 led by Bessemer Venture Partners, Team8, Hetz Ventures, and Brightmind, followed just four months later by a million Series A led by Notable Capital with participation from Startpoint Capital and Claltech, bringing total funding to million. The company employed approximately 30 people as of late 2025 and is headquartered in Tel Aviv, Israel.
Summary
It lists 11–50 employees. It has raised $60.0M in total across 2 rounds, most recently a $40.0M Series A round in Dec 2025. Investors include Team8, Notable Capital and Bessemer Venture Partners.
Tech & App Stack
6 technologies & apps tracked
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Funding History
Dec 2025
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Funding: Seed through Series A. Amounts, valuations, and investors where available.
Investors
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