Claire Diaz-Ortiz

Claire Diaz-Ortiz is a prominent figure in the venture capital and startup ecosystem, known for her multifaceted career as an early Twitter employee, a bestselling author, and an active investor. She operates in a dual capacity, engaging in personal angel investments while also serving as a Venture Partner at Concrete Rose, a venture capital firm dedicated to investing in exceptional founders from underrepresented backgrounds. Her investment philosophy is deeply rooted in leveraging technology for social good and fostering inclusive growth within the startup landscape.

As an investor, Diaz-Ortiz primarily focuses on early-stage companies, typically at the Seed or Pre-Seed rounds. Her portfolio spans a diverse range of sectors, including the future of work, consumer technology, and impact-driven ventures. She brings invaluable operational experience from her tenure as employee #12 at Twitter, where she played a pivotal role in the company's early growth and global expansion. This hands-on experience allows her to offer strategic guidance and mentorship to founders, extending beyond mere capital injection.

Her personal angel investment activity is significant, with public records and reports indicating investments in over 50 startups to date. These investments often reflect her commitment to diversity and innovation, supporting companies that are poised to disrupt industries while also creating positive societal impact. Through Concrete Rose, she participates in larger, institutional rounds, contributing to a fund that successfully raised a $15 million debut fund in 2020 and a $50 million second fund in 2022, underscoring her influence and reach within the broader venture capital community.

While specific figures for her individual angel checks can vary based on the stage and nature of the deal, her typical first check for personal investments generally falls within the range suitable for high-net-worth angel investors. She seeks to partner with founders who demonstrate strong vision, resilience, and a commitment to building scalable and impactful businesses. Her unique blend of operational expertise, extensive network, and a mission-driven approach makes her a highly sought-after investor for early-stage companies.