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Garry Tan and Sachin Agarwal, founders of Posterous (YC S08)Substack · 2017

Posterous · YC S08Substack · 2017

Tikhon Bernstam, co-founder of Parse (YC S11)Supabase (YC S20)

Parse · YC S11Supabase · YC S20

Sam Altman, founder of Loopt (YC S05)Snap Maps (2017)

Loopt · YC S05Snap Maps · 2017

Webvan delivery truck (1999)Instacart team at Nasdaq IPO (YC S12)

Webvan · 1999Instacart · YC S12

Startups die.
Ideas don't.

Every failed startup is a lesson for founders.

Deeply researched retros and rebuild playbooks.

Covering 1,835+ YC startups from 2005 to today

Featured Companies

S05
Acquired
Loopt logo

Loopt

Loopt, based in Silicon-Valley and backed by leading venture capital firms Sequoia Capital and New Enterprise Associates, has created an interoperable social-mapping service that allows individuals to use their location to discover the real world around them – enabling them to find and enjoy the people, places, and events that mean the most right here and now using their mobile phones. With Loopt, individuals will always know who’s around, what to do, or where to go

W06
Acquired
Wufoo logo

Wufoo

SaaS

Online form builder.

W07
Acquired
Heysan logo

Heysan

Community

Free messaging on mobile phones

S08
Acquired
Posterous logo

Posterous

Email

Dead simple blogs by email

S09
Acquired
Bump logo

Bump

Bump, Flock, Photoroll (unreleased) => Google Photos

W10
Acquired
Cardpool logo

Cardpool

Cardpool is a gift card exchange marketplace where anybody can buy, sell, or trade their new or pre-owned gift cards. Customers can buy gift cards up to 30% off their face value, sell their gift cards for up to 90% of their face value in cash, trade their gift cards for an Amazon.com Gift Card, or donate their gift card to charity. Cardpool provides free shipping for both buyers and sellers, a 100-day return policy, and policy of only selling gift cards that have no expiration date and no monthly fees.

W10
Acquired
Creative Market logo

Creative Market

Marketplace

Marketplace for graphic design assets

W10
Acquired
Optimizely logo

Optimizely

Marketing

The first all-in-one operating system for marketing

S10
Acquired
FutureAdvisor logo

FutureAdvisor

Fintech

The online financial management service for everyone.

W11
Inactive
Tutorspree logo

Tutorspree

Education

Online tutoring marketplace.

S11
Acquired
Codecademy logo

Codecademy

Education

The leading online learning platform for technical skills.

W12
Acquired
FarmLogs logo

FarmLogs

Analytics

Software that helps farmers operate more profitable businesses.

W12
Inactive
LendUp logo

LendUp

Fintech

LendUp is a socially responsible company on a mission to redefine…

W12
Inactive
Make School logo

Make School

Education

Make School is redesigning college for the 21st century. Students…

W12
Inactive
Pixelapse logo

Pixelapse

Design

Github for designers. We automatically keep track of revisions of…

W12
Inactive
The Muse logo

The Muse

Marketplace

The Muse is values-based job search & hiring for 7M+ monthly

S12
Acquired
Clever logo

Clever

Education

The platform that powers technology in the classroom.

W14
Acquired
Chargehound logo

Chargehound

FinOps

Automate your chargeback dispute process. (Acquired by PayPal)

W14
Acquired
SketchDeck logo

SketchDeck

Operating system for creative agencies

W14
Acquired
Wit.ai logo

Wit.ai

Developer Tools

Natural Language for Developers --Wit is an API that makes it easy…

W15
Acquired
Raven Tech logo

Raven Tech

Our vision is to build the next generation of iOS or Android, to…

S15
Acquired
Triplebyte logo

Triplebyte

SaaS

Intelligent technical hiring.

S16
Acquired
CrowdAI logo

CrowdAI

Machine Learning

CrowdAI is the world's leading no-code platform for vision AI

S16
Acquired
Saleswhale logo

Saleswhale

Artificial Intelligence

Saleswhale is an automated sales assistant that follows up with your…

S17
Acquired
Honeydue logo

Honeydue

Fintech

The simplest way for couples to manage money, together

W18
Inactive
Atrium logo

Atrium

LegalTech

Modern law firm for startups powered by proprietary technology

W18
Inactive
Storyline logo

Storyline

B2B

Create Alexa Skills without coding

W20
Inactive
Milo logo

Milo

Artificial Intelligence

The Family AI - a copilot for parents to tackle the invisible load of…

S21
Inactive
Opkit logo

Opkit

SaaS

AI phone calls for the US healthcare industry

S21
Inactive
Squire.ai logo

Squire.ai

Artificial Intelligence

Never code alone.

W23
Acquired
Booth AI logo

Booth AI

Artificial Intelligence

Generative AI Photographer for E-Commerce

W24
“Parted Ways”
Delve logo

Delve

SaaS

AI that makes compliance effortless

W07
Acquired
AU

Auctomatic

Auctomatic, a Y Combinator company, offers an auction and marketplace management system for all of those individual sellers on such sites as Ebay, Amazon, Overstock and others. The application lets you list your items as well as manage your sales, but it also helps you understand how to best optimize your selling and maximize profits. The company also received an investment from Paul Buchheit, the lead developer of Gmail.

S07
Acquired
AF

Anywhere.FM

Anywhere.fm lets you upload your music collection onto their site and then play your music anywhere from the web. They offer their own iTunes look-alike music player through which you can play your songs. The site also incorporates social networking aspects, allowing you to create your own profile and discover new music through Friend Radio.

S07
Inactive
RE

Reble

Music

P2P Music Sharing

W08
Acquired
OM

Omnisio

Video

Edit and enhance online video. Acquired by Google in July 2008.

S08
Inactive
JA

Job Alchemist

S09
Inactive
CW

CarWoo

Marketplace

The best way to buy a new car.

S09
Active
DE

Directed Edge

Artificial Intelligence

Product recommendations.

S09
Acquired
RD

RethinkDB

Open Source

The open source database for the realtime web.

W10
Inactive
AN

Answerly

There is no better way to engage with potential customers than by answering their questions. InboxQ makes it easy to find people who have questions about your business, products or general industry

W10
Inactive
MM

Mixed Media Labs

W10
Inactive
NE

Newslabs

NewsLabs offers a platform that looks to help "old school" journalists adapt to the web, by giving them help with advertising, SEO, and other issues they may not have had to deal with before.

W10
Acquired
ZE

Zencoder

Video

Video Encoding API, Open source video player (video.js)

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