Sebastian Wallin net worth
Quick answer
Sebastian Wallin's estimated net worth is $10.3M (range $7.21M – $15.46M) as of 2026. Sebastian Wallin is CTO at Castle. Castle valuation.
Sebastian Wallin is CTO at Castle (YC W16). Independent Entrepreneurial Check model estimate from public YC data.
At a glance
- Company status: Active
- Region: Sweden
- Industries: B2B, Security
- Team size: 20
- Website: https://castle.io
Who is Sebastian Wallin?
Sebastian Wallin is a founder associated with Castle in Y Combinator's Winter 2016 batch.
About Castle
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FAQ: Sebastian Wallin net worth and Castle valuation
What is Sebastian Wallin's net worth?
Sebastian Wallin's estimated net worth is $10.3M (range $7.21M – $15.46M) as of 2026. Sebastian Wallin is CTO at Castle. Entrepreneurial Check publishes an independent model-based estimate from public company and role data. Not verified net worth, and Entrepreneurial Check is not affiliated with Y Combinator or the profiled companies.
What is Castle valuation?
Castle's estimated valuation on Entrepreneurial Check is $92.0M. That valuation, or a disclosed round when one is public, is the source for the paper-wealth estimate. Independent model output — not a verified appraisal or official mark.
What is Sebastian Wallin's role?
Sebastian Wallin is CTO at Castle, a Y Combinator-backed startup (batch W16).