Mark Xu

Mark Xu is a Partner at Index Ventures, where he invests across all stages in enterprise software, cybersecurity, infrastructure, and artificial intelligence. Prior to joining the firm in January 2025, he spent three years as a growth investor at Lightspeed Venture Partners, deploying equity checks ranging from $50 million to $150 million. During his tenure at Lightspeed, Xu supported Series B and later funding rounds for prominent technology companies including Wiz, Glean, Grafana, Verkada, and Anduril. Before entering the venture capital industry, he worked in mergers and acquisitions at Citi and studied mathematics, economics, and computer science at Harvard University following his time as a violinist at The Juilliard School. Recognized as a rising star in venture capital by Business Insider in 2024, Xu currently focuses on partnering with technical founders to scale growth-stage enterprise and infrastructure platforms.