Eric O`Brien

Eric O`Brien

Active Investor

Co-Founder & Managing Director at Fall Line Capital

San Mateo, California

Eric O`Brien, Co-Founder & Managing Director at Fall Line Capital is an active investor based in San Mateo, California. This profile covers what Eric O`Brien backs, at which stage, and how founders can reach out in 2026.

Investor type
PE
Stages
Series BLate Stage Venture
Invests in
Artificial IntelligenceFintechHealthcare & BiotechBiotech & PharmaSaaS & EnterpriseConsumer & RetailE-commerce & D2CDeveloper Tools & Data
Location
San Mateo, California
Typical check
$5M
Past investments
16

Notable investments

Trace GenomicsPluto AIGranularPCHAsilomar BioSpiderbookAquantiaProject SliceGreenlight BiosciencesEvolv onDemandBenson Hill BiosystemsSwift Navigation

How to reach Eric O`Brien

Angels and operators like Eric O`Brien reply to specific, personalized notes that show real traction, not mass blasts. Build a verified list, write a note that fits their thesis, and track replies, all on Round Funded Accelerator.

Connect with Eric O`Brien

Application closes in --:--:--
Email Eric O`Brien

Frequently Asked Questions

What does Eric O`Brien invest in?

Eric O`Brien invests in Artificial Intelligence, Fintech, Healthcare & Biotech and Biotech & Pharma, typically at Series B and Late Stage Venture. Match your sector and stage, then reach out with a personalized pitch.

What stage does Eric O`Brien invest at?

Eric O`Brien typically invests at Series B and Late Stage Venture. Lead with traction that fits the stage when you reach out.

What is Eric O`Brien's typical check size?

Eric O`Brien typically writes checks around $5M. Use it as a signal for whether your raise fits their stage.

How do I contact Eric O`Brien?

Unlock Eric O`Brien's verified email on Round Funded Accelerator and send a personalized pitch. We surface only deliverable contacts so your outreach lands.

Application closes in --:--:--
Email Eric O`Brien