Greg Castle is a former consumer marketing and growth operator who led user acquisition at companies like Glassdoor and Chartboost before becoming a venture investor, giving him hands-on experience with performance marketing that most career financiers lack. He's known for deep specialization in spatial computing and AR/VR, where he was one of the earliest individual investors in Oculus at the seed stage and now focuses on frontier human-computer interfaces as a domain expert rather than a generalist investor. Greg Castle is a former consumer marketing and growth operator who led user acquisition at companies like Glassdoor and Chartboost before becoming a venture investor, giving him hands-on experience with performance marketing that most career financiers lack. He's known for deep specialization in spatial computing and AR/VR, where he was one of the earliest individual investors in Oculus at the seed stage and now focuses on frontier human-computer interfaces as a domain expert rather than a generalist investor.