Thomas Gieselmann co-founded Headline after moving from Germany to California in the late 1990s to build a data-driven, cross-continental venture platform, making him one of the early European founders who became long-term Silicon Valley GPs. He's known for becoming a customer before becoming an investor, often discovering companies by testing their products in his own life, and for preferring teams building full-stack operating systems for complex workflows rather than point solutions. Thomas Gieselmann co-founded Headline after moving from Germany to California in the late 1990s to build a data-driven, cross-continental venture platform, making him one of the early European founders who became long-term Silicon Valley GPs. He's known for becoming a customer before becoming an investor, often discovering companies by testing their products in his own life, and for preferring teams building full-stack operating systems for complex workflows rather than point solutions.