David Lieb and Aaron Epstein: Y Combinator's Controversies

It's a summer night in two thousand nine. "Dancing with the Stars" is on, Apple's "There's an app for that" ad airs... and a guy named David Lieb watches his servers die in real time.

Die how? Like, melt?

Like, a stampede. Every person watching that ad goes and downloads Bump, the app where you tap two phones together to swap contacts. Lieb's background is semiconductors. He does not know how to run servers at that scale.

So he's the guy who built the rocket but can't land it.

Basically. He messages his fellow Y Combinator founders. Within half an hour, Alex Polvi and his team from Cloudkick show up and bring it back online. That's Business Insider's telling.

Okay, lovely story. But the episode's called "Y Combinator's Controversies." Where's the scandal?

That's the loop I want you to hold. Because I went looking for controversies attached to David Lieb and Aaron Epstein specifically... and I want to be straight with you on air: there aren't any in the record.

None? You're starting an episode by telling me the premise is off?

I'd rather do that than invent one. What IS documented is a set of real controversies at Y Combinator, the institution these two men are now partners in. So the honest question is: what did they walk into?

Fine. Then tell me who they actually are first, because I don't know either name.

Lieb you half-met. Princeton and Stanford degrees in electrical engineering and computer science, researcher in the Stanford AI Lab, engineer at Texas Instruments. Then he gets into business school at Chicago Booth, and he and his friends build Bump.

Why does a guy like that even do an accelerator?

This is my favorite thing he's ever said. He told YC's blog they applied largely by accident, as an excuse to avoid getting a business school summer internship. Everyone else was interviewing at investment banks. They just wanted to write code.

That's the worst reason to start a company and it worked?

One hundred and fifty million people used Bump. He never went back for the second year. Dropped out with half an MBA. And then there's the interview that changed him. He's sitting across from Paul Graham in two thousand nine. Mid-answer, Graham puts his head down on the table.

Puts his head DOWN? That's brutal.

Then he looks up and asks: how is Bump going to be bigger than Google? Garry Tan says that one question is what made Lieb's ambitions grow.

Did it, though? Because Bump isn't a thing anymore.

Google bought it in twenty thirteen. And here's the turn: they had an unreleased photo-sharing app sitting in a drawer. That became Google Photos. Lieb led it past a billion users.

So the answer to "how will you be bigger than Google" was "I'll go be inside Google."

Aaron Epstein's arc is quieter and in some ways rarer. Creative Market, a marketplace for design assets, YC winter twenty ten. On Halloween twenty thirteen, by one account, two acquisition offers land the same day. One buyer would have dissolved the team. The other was Autodesk.

He takes Autodesk.

And then in twenty seventeen he negotiates it back OUT as an independent startup again. Bootstrapped, funded, accelerated, acquired, run inside a public company, spun out. Most investors have two of those chapters.

Okay. Now give me the controversies. The real ones.

Twenty twenty-one. YC has an internal forum called Bookface. Two founders — Paul Biggar of Dark and Katia Damer of Prolific — are removed from it after publicly criticizing YC. TechCrunch reported it. YC's position: they broke the rule against posting internal information externally.

And YC says that's... rare?

A dozen or so founders in sixteen years. But it opened a real argument about how a trust-based community handles dissent. YC's own ethics page says they can revoke founder status at their sole discretion.

Sole discretion is doing a LOT of work in that sentence.

Then twenty twenty-three. Ali Partovi of the Neo accelerator says at HackMIT that Neo has as many mentors as YC, for twenty startups instead of two hundred and fifty. Garry Tan accuses him on X of slander. Michael Seibel posts that he's "heard so so much dirt" on Partovi.

Publicly? A YC managing director?

Publicly. Partovi told TechCrunch he felt threatened, that he's never sued or threatened to sue anyone in tech, and that comparing yourself to an industry leader isn't slander.

So the controversies are institutional. Not these two guys.

Right. Lieb became a full group partner in April twenty twenty-four after three batches as a visiting partner. Epstein came in as a visiting partner in twenty eighteen, converted in twenty twenty. They're the people YC puts in the room with founders, not the people in the headlines.

Which, honestly, might be the point.

Here's the lesson I'd actually use. Lieb admits he let himself get distracted by big-name investors and App Store rankings. His line now: nothing ranks higher than customers coming back. He asks founders who they're building for — not a silhouette, real people with names — and when they last talked to them.

That's a question you could ask yourself about basically any job.

And it's the answer to the one Graham asked with his head on the table. You don't get bigger than Google by thinking about Google.