Early stage capital for lateral thinkers.
Joined November 2011
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- Followers 2,962
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317 Photos and videos
“@HarvardHBS is using chat and video avatars of its professors in an online boot camp... [@xfund faculty advisor] Elise Bates said the A.I. avatars gave students access to “low-stakes reps that they don’t get before they talk to a real investor.”
nytimes.com/2026/06/06/busin…
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We are honored to have been @Sirona_Medical and @camatsirona’s first seed investors. Today the company announces its partnership with @EverlightRad, the world’s largest tele-radiology provider!
May 28
One of the largest and most consequential partnerships in radiology IT history. Proud of our team and excited to work with Everlight.
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We are honored to have been @Sirona_Medical and @camatsirona’s first seed investors. Today the company announces its partnership with @EverlightRad, the world’s largest tele-radiology provider!
May 28
We're proud to announce our global partnership with @EverlightRad, the world's largest multinational teleradiology provider.
Everlight Radiology's 800 radiologists will use Sirona's RadOS platform to deliver AI-powered radiology across 350 hospitals on six continents. This is Sirona's first partnership outside the United States, and one of the largest radiology platform agreements ever signed.
Under the agreement, Everlight will replace its existing PACS and reporting stack across Australia, New Zealand, Ireland, the UK, the UAE, and South Africa — unifying diagnostic viewing, reporting, worklist, and AI into a single cloud-native platform accessible from any browser, anywhere.
As Everlight CTO Andy Donaldson put it: "For teleradiology, that architectural distinction is existential, not incremental."
We're just getting started. Read the full announcement: prnewswire.com/news-releases…
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If ever there was a founder here to win, it’s @AlexKiam191645 and @NeonAIResearch!
May 15
Competition is natural. We at @NeonAIResearch were there first and aren't going anywhere. We're here to win.
If you're a researcher looking for ethically sourced, speaker-separated, natural conversational audio sourced from our >500K registered users, DM me :)
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We are thrilled to have had the good fortune to be first investors in @alexhalliday and his team at @AirOpsHQ. Super excited for this launch!
May 13
Marketers who lean into AI search are about to have the best year of their career.
We built Quill to make sure of it.
@AirOpsHQ
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We are so honored to partner with @StevenGlinert and Sphere Semi as their seed investor. Today, the company announces a transformational deal with Northrop Grumman.
May 11
Today, Sphere Semi is announcing that our AI-designed chip is deploying into military hardware in partnership with Northrop Grumman.
This is the first AI-designed semiconductor to move from concept to deployment in a defense system.
A new era has begun. Full video below.
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Xfund retweeted
Mar 16
What got us from 0 to 1 isn't what will get us from 1 to N.
3 years ago, before the launch of ChatGPT, we set out to start a company that most people thought was impossible.
To be honest, many people still think it's impossible today.
Multiple rounds of rejection and external doubt later, we went from 0 to 1 and created the category of "Digital Minds". We built an exceptional team and earned the backing of investors like Sequoia and Founders Fund.
It wasn’t easy. There were probably moments we should have pivoted.
But we kept pushing.
Today we work with some of the top minds in their fields - @lennysan, @bhalligan, Eckhart Tolle, Vanessa Van Edwards, Dr. Mark Hyman.
Delphi is the place people go to learn from them, get their advice, and access their expertise.
Looking ahead, we believe Delphi is how every human will represent themselves in the AI age. A new way for people to meet, connect with, and learn from one another.
But to get there, we need to evolve.
Delphi is looking for a VP of Engineering - someone who has taken a consumer platform from 1 to N and knows the tradeoffs required to build infrastructure that supports millions. An AI-native builder and culture carrier.
In the early years, I had an almost allergic reaction to "experience" - I believed purely in slope over y-intercept. As we've scaled, I've come to understand that to get where we want to go, we need someone who has already been there.
If that's you, or someone you know, I want to talk.
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One of Xfund’s greatest honors is to have backed the archetypal liberal arts founder @DanielNadler twice -- in his first company @Kensho upon his graduation from @Harvard; and now, at @EvidenceOpen. nytimes.com/2025/10/20/busin…
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Xfund retweeted
25 Sep 2025
THE LIBRARY OF MINDS: EPISODE 1 - starring Keith Rabois (@rabois)
An OG member of the PayPal Mafia, co-founder at OpenDoor, Managing Director at Khosla Ventures, and one of Delphi's earliest believers.
We discuss:
• Lessons learned building PayPal, LinkedIn, Square, $OPEN & more
• Early career inflections: from litigation to Silicon Valley operator
• Why joining great teams is underrated, especially vs. starting your own company
• The new physics of AI startups (and org design mistakes to avoid)
• Why stretching & Slack are actually bad for you
Plus: What makes a winning office culture, advice for scaling from 20 to 100, building moats in AI, and why vacations might be overrated.
(00:00) — Intro
(00:56) — Who is Keith
(03:13) — Can you judge a startup by its office?
(04:28) — Litigator to PayPal Mafia, zero business experience
(08:52) — Start a company, or work for someone great?
(11:15) — All-nighters and culture at PayPal
(13:03) — Do vacations mean you hate your life?
(16:05) — Square’s zero-defect rule
(17:23) — Speed of adaptability vs. speed of execution
(21:35) — Is AI sustaining or disruptive?
(25:53) — Why stress is good for you
(28:14) — Building moats in AI
(30:39) — The downside of Slack
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We are so thrilled to have been @StevenGlinert and team’s first partners in Sphere Semi -- today the company announces its Series A to make AI-designed chips the default. If you’re in business operations, AI, and chip design: get in touch. We’re hiring!
22 Sep 2025
Proud to announce Sphere's fundraise on @tbpn today.
Our most recent financing round of $12M was led by @ACME and co-led by @Ventures_Future, bringing our total raised to $20m.
We ship highly performant chips that are entirely designed by AI.
Join us today. We're hiring.
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Our amazing portfolio company @withdelphi is about to blow your mind with its Library of Minds. This isn’t just another podcast - it’s the first interactive podcast where you can talk to the guest’s digital mind after the episode.
18 Sep 2025
What if you could call the founders of DoorDash, OpenDoor, Eventbrite, or HubSpot for advice - anytime?
The Library of Minds is the first interactive podcast. After each episode, continue the conversation by asking their Digital Mind on @withdelphi.
Ep 1 drops 9/25 👇
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We are so thrilled to have been @withdelphi’s seed investor. As co-founders @daraladje and @samspelsberg write, “Delphi is like a living Library of Alexandria—not just for famous thinkers, but for anyone with wisdom to share.” Check it out here: fastcompany.com/91356476/del….
24 Jun 2025
All the minds in the world. Now one question away.
We’ve raised $16M from @sequoia to build @withdelphi - create your digital mind & turn your expertise into living, interactive conversations that scale globally.
See how our customers use it below 👇🏼
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Harvard Business School just posted this video of our @xfund fireside chat with Aravind Srinivas! youtube.com/watch?v=Rkizxzta…
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With @HBSRock and @innovationlab, we were thrilled to bring @perplexity_ai CEO @AravSrinivas to Harvard in an electrifying series of events. Aravind was the guest judge at Xfund’s pitch competition and met with fellow scholars at Harvard and MIT. Students found him captivating!
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We are so proud to have been @DistSpectrum’s very first investors. The team is redefining electronic warfare for the 21st century.
18 Mar 2025
We’re excited to announce Distributed Spectrum’s $25M Series A—an oversubscribed round led by @saranormous, @ShieldCapVC , and @natfriedman with participation from existing investors, @felicis and @xfund, along with angels including leaders in technology, defense, and AI (@StanMcChrystal, @eglyman, Chris Re, @arashf, @stanine , @zakstone , and executives from Palantir).
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Xfund retweeted
4 Mar 2025
Introducing DELPHI ACTIONS
Your digital clone can now take automated actions based on user behavior.
Just describe what you want in plain language, and boom - our system builds the flows for you.
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What do people think *you* sound like? Try @boldvoiceapp’s amazing new accent guesser: and see if you can fool it by putting on your best foreign accent! start.boldvoice.com/accent-g…
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.@HarvardHBS just posted this video of Sam Altman at the @Xfund Experiment Assembly 2024. @patrickchung was Sam’s very first investor, and presented him with the first pitch deck he ever gave at age 19 in a packed event co-hosted by @HarvardHBS and @hseas: youtu.be/FVRHTWWEIz4?feature…
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