Harjavalta Oy is a Finnish family office and investment company founded in 1920, with offices in Harjavalta and Helsinki. It invests through Harjavalta Ventures in early-stage, internationally scalable startups, especially outside construction, and has direct private-company investment activity in Finland. Relevant sectors include energy, hardware, industrial technology, cleantech, climate, sustainability, manufacturing, real estate, infrastructure and deep tech; the group also holds long-term listed-company stakes.