Sebastian Siemiatkowski is the co-founder and chief executive officer of Klarna. See portfolio, sector focus and contact routes.
Sebastian Siemiatkowski is the co-founder and chief executive officer of Klarna, a Swedish fintech firm he launched in 2005, and he also serves as an angel investor and investment partner based in Stockholm. His investment thesis focuses on seed-stage companies in digital consumer services, particularly within fintech and transportation, with a geographic preference for Stockholm and Berlin. While specific check sizes are not publicly detailed, he operates as an angel investor who has completed approximately 14 to 15 investments, often joining rounds totaling significant capital. Notable portfolio companies include Klarna, Budbee, Truecaller, Scrive, and Omio (formerly Go Euro). Siemiatkowski’s distinctive point of view centers on scaling ecommerce payments and buy-now-pay-later solutions internationally, reflecting his own company-building experience in consumer finance. He has not published widely cited public writing on investing, but his portfolio choices consistently reinforce his focus on digital consumer infrastructure.
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