Jacob Rubens
Origination Partner at Flagship Pioneering
Cambridge, Massachusetts
Jacob Rubens, Origination Partner at Flagship Pioneering is an active investor based in Cambridge, Massachusetts. This profile covers what Jacob Rubens backs, at which stage, and how founders can reach out in 2026.
- Investor type
- VCInvestor
- Stages
- Early Stage VentureSeries A
- Invests in
- Healthcare & BiotechBiotech & PharmaFoodTech & Agriculture
- Location
- Cambridge, Massachusetts
- Typical check
- $750K
- Past investments
- 55
Notable investments
Denali Therapeutics
Syros Pharmaceuticals
Incredible FoodsQuotient TherapeuticsInzen Therapeutics
Ohana Biosciences
T2 BiosystemsTangent Medical Technologies
Kaleido BioSciences
Permeon Biologics
KovioHow to reach Jacob Rubens
Angels and operators like Jacob Rubens 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. "Jacob Rubens." Round Funded investor database, updated September 9, 2026.
Stable URL, it will not change: https://www.roundfunded.com/en/investor/jacob-rubens
Frequently Asked Questions
What does Jacob Rubens invest in?
Jacob Rubens invests in Healthcare & Biotech, Biotech & Pharma and FoodTech & Agriculture, typically at Early Stage Venture and Series A. Match your sector and stage, then reach out with a personalized pitch.
What stage does Jacob Rubens invest at?
Jacob Rubens typically invests at Early Stage Venture and Series A. Lead with traction that fits the stage when you reach out.
What is Jacob Rubens's typical check size?
Jacob Rubens typically writes checks around $750K. 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.