Jonathan Langer, Founder of Act Security

About Jonathan Langer

Jonathan Langer is the founder of Act Security. Act Security operates in Cybersecurity and is based in Tel Aviv, Israel. Act Security has raised $60M, latest Series A $40M (2025). Backers on record include Rares Crisan, Notable Capital.

Jonathan Langer at a glance

Company

Act Security

Industry

Cybersecurity

Location

Tel Aviv, Israel

Total raised

$60M

Investors on record

Rares Crisan, Notable Capital

Frequently asked about Jonathan Langer

Who is Jonathan Langer?

Jonathan Langer is the founder of Act Security. Full profile, funding history and background on StartupFundraising.com.

What company did Jonathan Langer found?

Jonathan Langer founded Act Security, a Cybersecurity company based in Tel Aviv, Israel.

How do I contact Jonathan Langer?

Verified contact routes, background and funding history for Jonathan Langer are available on the StartupFundraising.com founder profile.

This founder profile draws on disclosed rounds, filings and investor records in the StartupFundraising database and is updated as new funding is recorded. Founders raising now use profiles like this one to study comparable Cybersecurity journeys in Tel Aviv — who backed them, at what stage, and how much they raised.

Act Security funding profile (1)

• Act Security funding: total raised, rounds and investors

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