Sebastian Siemiatkowski

Active Investor

Co-Founder / CEO

Stockholm, Stockholm County

Sebastian Siemiatkowski, Co-Founder / CEO is an active investor based in Stockholm, Stockholm County. This profile covers what Sebastian Siemiatkowski backs, at which stage, and how founders can reach out in 2026.

Investor type: AngelInvestment Partner
Stages: Seed
Invests in: Developer Tools & Data
Location: Stockholm, Stockholm County
Typical check: $250K
Past investments: 8

Notable investments

NylasPrionScriveDepopOmioKlarnaStevenBudbee

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Frequently Asked Questions

What does Sebastian Siemiatkowski invest in?

Sebastian Siemiatkowski invests in Developer Tools & Data, typically at Seed. Match your sector and stage, then reach out with a personalized pitch.

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