Mattan Griffel
FounderFounder at Ophelia · Founder/CEO at One Month
Brooklyn, New York, United States
FoundedOne Month · YCOphelia · YC
About
Mattan Griffel studied philosophy and finance at New York University and co-founded Ophelia, a Y Combinator-backed opioid recovery platform. He is faculty at Columbia Business School and an Innovation Fellow at the Lang Center for Entrepreneurship.
Likely email· guessed from name + firm domain, not firm-published
- m•••@ophelia.comreveal75% confident
Founder at OpheliaYC W20
Intro paths
YC
Mattan went through Y Combinator (Winter 2020) — any YC alum in your network can reach them through the YC community.
→
In turn, Mattan can intro founders to Ophelia's investors below.
Ophelia's investors · 8
Four Acres CapitalNew York · $50K – $100K checksGeneral CatalystSan Francisco · $30M checksGood FriendsSan Francisco · $250K – $1M checksInterplay Ventures Early Stage Management LlcNew York · $1M checksMenlo VenturesSan Francisco · $1M – $20M checks · since 2021Refactor CapitalBurlingame · $1M – $2M checksTiger Global ManagementNew York · $1M – $100M checksY CombinatorSan Francisco · $500K checks · since 2020
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Co-founders at Ophelia
ZG
Zack GrayFounder
Founder/CEO at One MonthYC S13
Intro paths
YC
Mattan went through Y Combinator (Summer 2013) — any YC alum in your network can reach them through the YC community.
→
In turn, Mattan can intro founders to One Month's investors below.
One Month's investors · 2
Co-founders at One Month
CC
Chris CastiglioneFounder
Experience
- Columbia Business SchoolAssistant Professor of Professional Practicecurrent2025 — presentNew York, United States
- Columbia Business SchoolAdjunct Assistant Professor of Business2016 — 2025Greater New York City Area
- Eugene M. Lang Entrepreneurship Center at Columbia Business SchoolLang Entrepreneurship Coachcurrent2023 — present
- OpheliaBoard Observercurrent2023 — presentNew York, United States
- OpheliaCo-Founder, President, & COO2019 — 2023New York, United States
- YPOMembercurrent2021 — present
- InvisiblePartner, SVP2024 — 2025
- InvisibleAdvisor2023 — 2024
- Eugene M. Lang Entrepreneurship Center at Columbia Business SchoolLang Center Innovation Fellow2019 — 2021New York, United States
- One MonthChairman2017 — 2021Greater New York City Area
- One MonthCo-Founder & CEO2013 — 2017Greater New York City Area
- SandboxNYC Ambassador2010 — 2020Greater New York City Area
- GrowHackPartner2012 — 2016Greater New York City Area
- The Front LabsCEO & Founder2011 — 2013Greater New York City Area
- appssavvyHead of Marketing2010 — 2011Greater New York City Area
Skills & more
Ruby on Rails4Fundraising3Leadership Development Coaching3Executive Coaching1Healthcare1Social Media99Marketing84Advertising17Philosophy6Start-ups99Digital Media28Digital Strategy33
+12 more
Digital MarketingSocial Media MarketingEntrepreneurshipOnline AdvertisingAnalyticsMarketing StrategyWeb AnalyticsBusiness DevelopmentProduct DevelopmentLeadershipStrategyStrategic PlanningLanguages English · German
- One Month Rails — One Month
From Mattan's professional profile.
Frequently asked questions
- Who is Mattan Griffel?
- Mattan Griffel studied philosophy and finance at New York University and co-founded Ophelia, a Y Combinator-backed opioid recovery platform. He is faculty at Columbia Business School and an Innovation Fellow at the Lang Center for Entrepreneurship.
- Where does Mattan Griffel work?
- Mattan Griffel is Founder/CEO of One Month and Founder at Ophelia.
- What companies did Mattan Griffel found?
- Mattan Griffel founded One Month, Ophelia.
- Where did Mattan Griffel go to school?
- Mattan Griffel studied at Y Combinator (Summer 2013, Winter 2020); Columbia Business School (Master of Business Administration (MBA)); NYU Stern School of Business (Bachelor of Science (BS), Double Major: Finance & Philosophy).
Founder mafias
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Columbia Business School mafia66
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NYU Stern School of Business mafia50
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Ophelia mafia4
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Same school
Also attended Y Combinator2,000
Tarek MansourCo-founder & CEO of KalshiSuhail DoshiFounder of Mixpanel; founder of ParticleSubomi OluwalanaCo-founder & CEO of ConvoyMaroof AhmedFounder at Octopus VenturesJustin SwartPartner at Bitkraft Esports VenturesCollin WallaceGeneral Partner at Lobby Capital
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Also attended Columbia Business School668
Ryan PetersenFounder & CEO of FlexportAryo TehranianManaging Director at Mayfair Equity PartnersYibo NianInvestment Director at Intel CapitalKesha CashFounder & General Partner at Impact America FundMahati SridharPartner, Rise of the Rest at RevolutionGiuseppe IademarcoHead of Global Partnership at P101 Ventures
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Luna SchmidInvestor at GV (Google Ventures)Kaz TeradaVenture Advisor at Monta Vista CapitalNeil FongManaging Director Asia at Burda Principal InvestmentsAlex TosoliniAdvisor at CincyTechMax WechterSenior Director of AI at Lerer HippeauKrupa VankayalaPartner, People & HR at Sapphire Ventures
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Shared employers
Also worked at Columbia Business School96
Jeremy PhilipsInvestor at Spark CapitalGraham BrownManaging Partner at Lerer HippeauCharlie RexfordChief of Staff to CEO at Sapphire VenturesSiddharth RamakrishnanPrincipal at Scale Venture PartnersHalle TeccoFounder, Rock Health & Natalist at Giant Ventures Global LlpFlorin MihocVenture Partner at Ff Venture Capital
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