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Startup · United Kingdom

Callosum

HQ London, United KingdomFounded 202511-50 employeesUpdated

Callosum builds systems-level infrastructure enabling diverse chips and AI models to work as a unified intelligent system.

Startup
Website
Total raised
$110M
3 rounds
Last round
$100M
Seed · Aug 20, 2026

Funding3 rounds · $110M

Equity raised
$110M
Debt, secondaries & grants
$2.9M
Latest
$100MSeed · Aug 20, 2026
Cumulative raised$110M
Feb 26, 2026Aug 20, 2026

Raised counts equity rounds; debt, secondary sales and grants are totaled separately. Amounts in other currencies are converted at the announcement month's average rate. A ~ marks an estimated or converted amount.

People2

All 2 people →

Related Organizations

Sources9

Profile4

  1. 1
    CompanyCallosum

    Callosum · Supports Organization · name

    “Callosum”
  2. 2
    DatabaseCallosum - Crunchbase company profile

    Crunchbase · Supports Organization · employee range

    “employee_range: 11-50 (profile: 11-50)”
  3. 3
    NewsLondon-based Callosum raises EUR 85.4 million in Atomico-led Seed round

    EU-Startups · Supports Organization · founded year

    “Founded in 2025 by Jascha Achterberg and Danyal Akarca”
  4. 4
    DatabaseCallosum - LinkedIn company profile

    LinkedIn · Supports Organization · employee range

    “employee_range: 11-50 (profile: 11-50 employees)”

Funding4

  1. 5
    Company$100M Seed to Redefine How Humanity Computes

    Callosum · Aug 20, 2026 · Supports Funding round, Funding round · amount

    “The round is led by Atomico with significant participation from Plural, DCVC, and the UK Sovereign AI Fund”
  2. 6
    NewsCallosum raises $10.25M for multi-chip AI infrastructure

    The Next Web · Feb 26, 2026 · Supports Funding round

    “led by European early-stage venture fund Plural”
  3. 7
    CompanyWe Are Scaling Heterogeneous Compute

    Callosum · Feb 26, 2026 · Supports Funding round · amount

    “ARIA has awarded Callosum $2.9M to pioneer R&D on the first co-located heterogeneous compute cluster for multi-agent intelligence”
  4. 8
    NewsCallosum raises $100M seed round

    Tech.eu · Supports Funding round · amount

    “It follows Callosum raising $10.25m in February this year when it came out of stealth.”

People1

  1. 9
    OtherBlack Flag 100.2

    Black Flag · Supports Organization, Role

    “Callosum builds systems-level infrastructure enabling diverse chips and AI models to work as a unified intelligent system. By co-evolving the chip and”

Each fact on this page is attached to the sources that support it. Archived copies are linked when we keep one.