Reaction
Venture capitalSeed–Late Stage · 11 people tracked
Investment thesis
Reaction aims to drive exponential change by scaling innovations that improve lives and address urgent global problems. Its first fund, W250 Venture, backs proven leaders with world-changing potential in mission-aligned sectors such as health technology and climate innovation, and works to scale their innovations globally. Its second fund focuses on climate, globally scaling top Stanford climate innovations to accelerate progress toward net zero across the industries they can impact.
Source: firm website, verified Aug 3, 2026.
Team · 11 people
from the firm's websiteWhat they invest in
from 2 of 2 portfolio companiesBiotech ×1Circular Economy ×1Climate Tech ×1GovTech ×1New Materials ×1
HQs:United States×2
Investments · 2 tracked
founders shown can be your intro pathMango Materials develops biopolymers and biocomposites as sustainable alternatives to conventional plastics for consumer and industrial applications.
BiotechCircular EconomyClimate TechNew MaterialsVacaville, US
Co-investorsAlante CapitalCollaborative FundGlobal BrainVox CapitalGratitude Railroad
Zenysis develops data integration software that enables government agencies to consolidate and analyze information across multiple sources for decision-making during emergencies and crises.
GovTechSan Francisco, US
Jonathan Stambolis(Founder/CEO)inIan Webster(Founder/CTO)in
Co-investors500 GlobalY Combinator
Frequently asked questions
- What stage does Reaction invest at?
- Reaction invests at the Seed, Series A, Late Stage stages.
- What sectors does Reaction focus on?
- Reaction focuses on Climate Tech, Healthtech, Impact & Social Good.
- Does Reaction lead rounds?
- Reaction typically participates in rounds rather than leading them.
- Who does Reaction co-invest with?
- Reaction most often shares deals with 500 Global, Alante Capital, Collaborative Fund, among 6 tracked co-investors.
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