Mark Jacobsen
Managing Director at O'Reilly AlphaTech Ventures
San Francisco, California
Mark Jacobsen, Managing Director at O'Reilly AlphaTech Ventures is an active investor based in San Francisco, California. This profile covers what Mark Jacobsen backs, at which stage, and how founders can reach out in 2026.
- Investor type
- VCMicro VCPE
- Stages
- Early Stage VenturePre SeedSeed
- Invests in
- CybersecurityDeveloper Tools & DataEdTechRobotics & AutomationMedia & ContentAR/VR & MetaverseMarketplaceSaaS & Enterprise
- Location
- San Francisco, California
- Typical check
- $250K
- Past investments
- 57
Notable investments
FoursquareLearnZillionCampagoSherpaaFidelis
Bloom StudioMaker Media
3D RoboticsScrollCotton Bureau
RiffynHow to reach Mark Jacobsen
Angels and operators like Mark Jacobsen 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.
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About this profile
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Cite this page
Round Funded. "Mark Jacobsen." Round Funded investor database, updated September 9, 2026.
Stable URL, it will not change: https://www.roundfunded.com/en/investor/mark-jacobsen
Frequently Asked Questions
What does Mark Jacobsen invest in?
Mark Jacobsen invests in Cybersecurity, Developer Tools & Data, EdTech and Robotics & Automation, typically at Early Stage Venture, Pre Seed and Seed. Match your sector and stage, then reach out with a personalized pitch.
What stage does Mark Jacobsen invest at?
Mark Jacobsen typically invests at Early Stage Venture, Pre Seed and Seed. Lead with traction that fits the stage when you reach out.
What is Mark Jacobsen's typical check size?
Mark Jacobsen typically writes checks around $250K. Use it as a signal for whether your raise fits their stage.
How do founders reach investors like this?
Round Funded lists active investors with verified, professional contact details for signed-up founders. Filter by sector, stage and location, then send a personalized pitch from your own inbox.
What is Round Funded?
Round Funded is an investor database and outreach platform for startup founders. It lists 60,000+ active investors with verified contacts, filtered to recent investment activity, and lets founders send personalized pitches from their own Gmail, track replies, and share a free Data Room. Round+ starts at $99 per month with a 3-day trial.