Castor Ventures operates as an MIT-only alumni venture fund that requires investors to be MIT alumni and offers both a fully managed annual fund plus a live syndicate where individual alumni can opt into specific deals with access to internal diligence. The fund applies a strict co-invest-only model targeting 5-15% allocations alongside elite firms like Andreessen Horowitz and Sequoia, while leveraging Alumni Ventures' 850,000+ person network and 1,300+ portfolio companies to provide portfolio support far beyond what typical small alumni funds can offer.