Mark Jacobstein

Investment Stage

Focus Areas

About Investor

Mark Jacobstein is Co-Founder and General Partner at Near Horizon (Palo Alto, CA, founded 2023), a hands-on early-stage venture studio that co-founds and builds AI and health-tech startups from day zero — providing both capital ($500K-$1.2M) and deep operational partnership to founders building AI-powered companies. He is also a Visiting Partner at South Park Commons (February 2026). He brings 30+ years of entrepreneurial experience building 11 companies, raising $1.3B+, and executing 8 exits. Career highlights: founded Small World Sports (1994 — world's first online fantasy sports company); co-founded Digital Chocolate with Trip Hawkins (mobile gaming pioneer); joined Sam Altman at Loopt; led iSkoot through acquisition by Qualcomm; Chief User Engagement Officer at Guardant Health (led $500M+ pre-IPO fundraising through IPO); Chief Business Officer at Immunai; co-founded Jimini Health (AI mental health). Portfolio at Near Horizon includes Sleuth Insights and Clara (Financial Software). Education: Harvard College (Class of 1992). Lives on the Stanford campus with family.