Mark Ein

Active Investor

Founder & Owner at Washington Kastles

Washington, District of Columbia

Mark Ein, Founder & Owner at Washington Kastles is an active investor based in Washington, District of Columbia. This profile covers what Mark Ein backs, at which stage, and how founders can reach out in 2026.

Mr. Mark Ein serves is the Founder and serves as Chief Executive Officer & Chairman at Venturehouse Group. He serves as Board Member at Custom Truck One Source. He serves as Executive Chairman at Kastle Systems International. He is an investor, entrepreneur, and philanthropist with over 24 years of experience building growth companies across diverse industries. He served as the Chairman and CEO of Capitol Investment Corp.VI. He currently served as the Chairman and CEO of Capitol Investment Corp. V, and VII and previously held similar roles at Capitol Investment Corp. I, II, III, and IV. His SPACs have completed successful business combinations with firms including Lindblad Expeditions and Two Harbors Investment Corp. He is also the Founder and CEO of Washington Esports Ventures and President of Leland Investments Inc.,. He is Co-Chairman of Kastle Holding Company LLC, the parent of Kastle Systems, His investment firm, Venturehouse, has backed companies such as XM Satellite Radio, Matrics Technologies, Cibernet Corporation, and VSGi. He founded the Washington Kastles, His earlier career includes positions at The Carlyle Group, Brentwood Associates, and Goldman Sachs. He currently serves on the boards of AgroFresh Solutions, VSGi, the District of Columbia Public Education Fund (as Chairman), and the United States Tennis Association. He has also held board roles at Doma Holdings, Kirlin Design Build, Suwannee Lumber, and Colson Group. He holds an MBA from Harvard Business School and earned a Bachelor of Science in Economics and Finance from the University of Pennsylvania's Wharton School in 1987.

Investor type: Angel
Stages: Early Stage VenturePre SeedLate Stage Venture
Invests in: SaaS & EnterpriseSports & Fitness
Location: Washington, District of Columbia
Typical check: $500K
Past investments: 6

Notable investments

WEconnect Health ManagementSnaps (Business/Productivity Software)Ex ParteSocialRadarPlaySight InteractiveBasket Savings

How to reach Mark Ein

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Frequently Asked Questions

What does Mark Ein invest in?

Mark Ein invests in SaaS & Enterprise and Sports & Fitness, typically at Early Stage Venture, Pre Seed and Late Stage Venture. Match your sector and stage, then reach out with a personalized pitch.