25 YC Companies in the S09 Batch (Summer 2009)
Y Combinator's Summer 2009 batch (S09) has 25 companies in this directory. Below is every one of them: what it does, where it is based, its status today, and a link to its YC application reconstructed in the real form, so you can read how S09 founders described their companies before they got in.
- Companies
- 25
- Top industries
- Consumer, B2B and Real Estate and Construction
- Top locations
- San Francisco, Mountain View and Palo Alto
- YC top companies
- 2
Read the YC application of all 25 companies
- Every company's YC application, reconstructed in the real form
- Filter every batch by industry, country and team size
- Then find the investors who fund startups like yours
The first 25 companies, top companies first
That is 10 of 25.
Every company below has its YC application reconstructed in YC Insights. Create a free account to read them all.
Applying to YC? Study these applications first.
YC Insights holds the reconstructed application of every company on this page, filterable by batch, industry and country, next to 60,000+ investors who fund startups like yours.
About this list
This list is part of Round Funded, an investor database and outreach platform for founders. It covers 60,000+ active VCs, angels, family offices and accelerators with verified contacts, lets you send pitches from your own Gmail, and includes a free Data Room for your raise.
Frequently Asked Questions
How many Y Combinator companies are in the Summer 2009 batch?
This directory lists 25 YC companies in the Summer 2009 batch, out of 6,207 across every batch since 2005. The count updates when the directory is refreshed, and every one of them is on this page with a link to its public profile.
Are the YC applications on these pages real?
No. YC keeps submitted applications private. Every application linked from this list is a reconstruction: the real YC form questions, answered from the company's public data. The Company section is free on each page; the rest opens in YC Insights.
Which companies on this page are best known?
Mixpanel and WePay lead the table above. YC marks 2 of the 25 companies here as top companies, its own list of the highest-valued and highest-revenue alumni.
How do I use this list when applying to YC?
Pick five companies on this page whose product is closest to yours, read their reconstructed applications side by side in YC Insights, and note how each answers the same question. Then write your own answers to that standard.
Where does this data come from?
From YC's public company directory, refreshed by batch, with each company's status, industry and location as YC reports them. Round Funded adds the reconstructed application and the founder profiles; nothing private is published.
What is Round Funded?
Round Funded is an investor database and outreach platform for startup founders. It lists 60,000+ active investors with verified contacts, filtered to recent investment activity, and lets founders send personalized pitches from their own Gmail, track replies, and share a free Data Room. Round+ starts at $99 per month with a 3-day trial.