Castle is a privately held company. It is backed by 4 investors on record, including Index Ventures and First Round Capital.

Where is Castle headquartered?

Castle is headquartered in San Francisco, United States.

Who is the CEO of Castle?

Johan Brissmyr is the CEO of Castle.

Johan Brissmyr and Sebastian Wallin are co-founders of Castle, founded in 2015.

What products does Castle sell?

Castle sells Castle Device Intelligence.

Castle

Fraud & Payment SecuritySan Francisco, United Statesfounded 2015privatecastle.io ↗

Castle is a cybersecurity company specializing in Fraud & Payment Security, founded in 2015 and headquartered in San Francisco, United States. It has raised $11.56M in equity across 5 priced rounds, employs about 54 people, and is privately held.

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updated Oct 11, 2026

Latest Castle news and company activity

What Castle did, dated — selected moves from the record, one per kind, newest first.

Apr 2020RecognitionCastle Named a 2020 "Best Place to Work in the Bay Area"
Sep 2019PartnershipHow Castle is Building Codeless Customer Account Protection

5 events tracked since Sep 2019 · selected events shownUnlock the complete Castle timeline

Castle Momentum score

40/ 100

Mandos Momentum blends hiring, funding, traffic and sentiment into one score out of 100. The score is free; the pillars behind it unlock in the platform.

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Castle products

Castle Device IntelligenceDevice fingerprinting and intelligence for account security and fraud detectionDetails ↗

Castle funding

Castle has raised $11.56M in priced equity. Its most recent round was a Venture Round in January 2021. It has 5 funding rounds on record: Seed, Seed, Seed, Series A, and Venture Round. 4 investors are on record, including Index Ventures and First Round Capital.

Equity raised: $11.56M5 priced rounds
Last round: Venture RoundJan 2021

View the complete funding history

Castle employees and hiring

As of September 2026, Castle has about 54 employees.

Employees: 54
30-day change: 0%
Open roles: 0

See hiring trends

Castle competitors

Competitors of Castle include MirrorTab. The full competitive set, with overlap scoring, is in the platform.

MirrorTab

ranked by CybersecTools comparison demand, 90 days

View the competitive set with overlap scores

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The other 440 data points.

Funding historyevery round, every investor named
Headcount growthvelocity, departments, seniority
Open jobslive postings, hiring pace, role mix
Tech stackframeworks, clouds, security
Competitorsfull set, overlap scored
Leadershipevery exec, with roles
Customersnamed publicly, with sources
Reviews & newssentiment, coverage, cadence

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Funding, round by round, with the investors
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The other 440 data points.

Funding historyevery round, every investor named
Headcount growthvelocity, departments, seniority
Open jobslive postings, hiring pace, role mix
Tech stackframeworks, clouds, security

Similar in Fraud & Payment Security

Common questions about Castle.

How much funding has Castle raised?: Castle has raised $11.56M in priced equity. Its most recent round was a Venture Round in January 2021. It has 5 funding rounds on record: Seed, Seed, Seed, Series A, and Venture Round. 4 investors are on record, including Index Ventures and First Round Capital.
How many people work at Castle?: As of September 2026, Castle has about 54 employees.
Who owns Castle?: Castle is a privately held company. It is backed by 4 investors on record, including Index Ventures and First Round Capital.
Where is Castle headquartered?: Castle is headquartered in San Francisco, United States.
Who is the CEO of Castle?: Johan Brissmyr is the CEO of Castle.
Who founded Castle?: Johan Brissmyr and Sebastian Wallin are co-founders of Castle, founded in 2015.
Who are Castle's competitors?: Competitors of Castle include MirrorTab. The full competitive set, with overlap scoring, is in the platform.
What does Castle do?: Castle is a cybersecurity company specializing in Fraud & Payment Security, founded in 2015 and headquartered in San Francisco, United States.