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Justin Butler

InvestorFounder

Partner at Eclipse Ventures · Founder at Nucleusrad

San Francisco Bay Area

Writes $200K – $5M checks · typically $2.5M

FoundedNucleusrad

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Contact· self-published, not guessed

Founder at Nucleusrad

Intro paths

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In turn, Justin can intro founders to Nucleusrad's investors below.

Nucleusrad's investors · 3

EclipsePalo AltoEclipse VenturesPalo Alto · $200K – $5M checks · since 2022OrbiMedNew York · $1M – $75M checks · since 2026

Co-founders at Nucleusrad

GB
Geoffrey B. JohnsonFounder

Investments

Per curated public sources.

Colleagues at Eclipse Ventures

Aidan Madigan-Curtis
Partner at Eclipse Ventures
Allyson Johnson
Partner at Eclipse Ventures
Amir Frenkel
Venture Partner at Eclipse Ventures
Angela Hayward
Partner and Head of Strategy at Eclipse Ventures
Charly Mwangi
Partner at Eclipse Ventures
Erin Greenwood
Senior Executive Assistant and Events Coordinator at Eclipse Ventures
Esther Kim
Director of Community Operations at Eclipse Ventures
Gareth Kaczkowski
Investor at Eclipse Ventures

Network1

Alex Rigopulos
Investor at Harmonix Music Systems

Investors connected to Justin in public investor directories — a warm-intro map.

Frequently asked questions

Who is Justin Butler?
Partner at Eclipse Ventures
Where does Justin Butler work?
Justin Butler is Founder of Nucleusrad and Partner at Eclipse Ventures.
What check size does Justin Butler write?
Justin Butler typically writes checks of $200K – $5M.
What companies did Justin Butler found?
Justin Butler founded Nucleusrad.
What companies has Justin Butler invested in?
Investments tracked here include Brightinsight, Capstan, Cellares, Common Networks, Nucleusrad, Rune Labs, Safely You, Signal Laboratories, Syng, Tortuga logic, Inc. dba Cycuity, Watchmaker Genomics.

Founder mafias

About this profile. Compiled from public sources — Eclipse Ventures's own website and public professional profiles — and summarised by Fundraising Fox; every fact is kept with where it came from. Spotted an error, or would rather not be listed? Email privacy@fundraisingfox.com · How we build profiles · Your rights