Theodosian is a privately held company. It is backed by 5 investors on record, including Fuel Ventures and D11Z Ventures.

Where is Theodosian headquartered?

Theodosian is headquartered in London, United Kingdom.

Who is the CEO of Theodosian?

Brendan King Diaz is the CEO of Theodosian.

Who founded Theodosian?

Brendan King Diaz and Andy Johnson are co-founders of Theodosian, founded in 2025.

Theodosian

Data ProtectionLondon, United Kingdomfounded 2025privatetheodosian.com ↗

Theodosian is a cybersecurity company specializing in Data Protection, founded in 2025 and headquartered in London, United Kingdom. It has raised $1.3M in equity across 1 priced round, employs about 8 people, and is privately held.

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updated Oct 11, 2026

Latest Theodosian news and company activity

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

Jul 2026RecognitionTheodosian named in Wavestone UK Cybersecurity Startup Radar 2026
Jul 2026RecognitionTheodosian wins BRYCK Startup Alliance Accelerator, earns ticket to Slush Helsinki
Oct 2025Product launchIntroducing Theodosian | Data-Centric File Security
Oct 2025Funding roundCybersecurity startup Theodosian secures $1.3M pre-seed led by Fuel Ventures

Theodosian Momentum score

66/ 100

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Theodosian products

TheodosianFile-level encryption and access control for data-centric securityDetails ↗

Theodosian funding

Theodosian has raised $1.3M in priced equity. Its most recent round was a Pre-Seed in October 2025. 5 investors are on record, including Fuel Ventures and D11Z Ventures.

Equity raised: $1.3M1 priced round
Last round: Pre-SeedOct 2025

View the complete funding history

Theodosian employees and hiring

As of September 2026, Theodosian has about 8 employees.

Employees: 8
Open roles: 0

See hiring trends

Theodosian competitors

Competitors of Theodosian include Fasoo, Seclore, and SealPath. 1 more is in the platform, with overlap scoring.

matched by product category and features

View all 4 competitors 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
Headcount, hiring and the people
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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 Data Protection

Common questions about Theodosian.

How much funding has Theodosian raised?: Theodosian has raised $1.3M in priced equity. Its most recent round was a Pre-Seed in October 2025. 5 investors are on record, including Fuel Ventures and D11Z Ventures.
How many people work at Theodosian?: As of September 2026, Theodosian has about 8 employees.
Who owns Theodosian?: Theodosian is a privately held company. It is backed by 5 investors on record, including Fuel Ventures and D11Z Ventures.
Where is Theodosian headquartered?: Theodosian is headquartered in London, United Kingdom.
Who is the CEO of Theodosian?: Brendan King Diaz is the CEO of Theodosian.
Who founded Theodosian?: Brendan King Diaz and Andy Johnson are co-founders of Theodosian, founded in 2025.
Who are Theodosian's competitors?: Competitors of Theodosian include Fasoo, Seclore, and SealPath. 1 more is in the platform, with overlap scoring.
What does Theodosian do?: Theodosian is a cybersecurity company specializing in Data Protection, founded in 2025 and headquartered in London, United Kingdom.