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YC S11 companies (Summer 2011)

All 60 companies in Y Combinator's Summer 2011 batch, with team size, growth, open roles and funding.

Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.

Hiring the mostlast 60 days
8 roles
ApolloS11
  1. 2OneSignal8
  2. 3Sift4
See all 6
Fastest growingteam, 6 months
+30%
MixRankS11
  1. 2Sift+6%
  2. 3Streak+5%
See all 4
Shrinkingteam, 12 months
−13%
ApolloS11
  1. 2Vidyard−12%
  2. 3Sift−12%
See all 6
Companies
60
Active
12
Hiring, last 60 days
6
Open roles, 60 days
25
People on these teams
6,831
Showing 50 of 60 companies
CompanyTeam6 mo12 moOpen rolesTotal raisedLast round
Change the world to value skills over pedigree
2,231+4%+14%3$103MSeries D$60M, Mar 2022
We’re building the world’s bank payment network.
862+1%+2%0$529MSeries G$312M, Feb 2022
Music Intelligence
839+5%+12%0$77.7MUndisclosed round$5.8M, Sep 2020
Language learning through video chat.
493+1%0%0$1MSeed$1M, Dec 2014
LeadGenius is an account-based marketing and lead generation…
398−3%−3%0$30.4MSeed$3M, Sep 2019
The leading online learning platform for technical skills.
391−2%−9%0$87.5MSeries D$40M, Feb 2021
The Leader in Digital Trust & Safety
283+6%−12%4$157MSecondary$50M, Feb 2022
Uber for food.
278+1%+1%0$15MSeries A$13M, Apr 2014
Apollo helps engineering teams accelerate delivery
166−2%−13%8$183MUndisclosed round$130M, Mar 2022
Engage customers through personalized omni-channel messaging
165−5%−1%8$82MSeries C$50M, Jan 2023
Video for business.
148−6%−12%1$90.9MUndisclosed round$15.2M, Apr 2024
Powering scientific outsourcing
129+4%+8%0$77.5MUndisclosed round$20M, Oct 2019
Data products for sales, marketing, finance, recruiting, and more.
100+30%+117%YC$2MDebt$250K, Feb 2016
Marketplace for life science supplies.
94−1%+4%1$50.2MDebt$23M, Apr 2026
Parse is the easiest way to build apps.
930%0%0$7MPre-seed$5.5M, Oct 2022
The platform for your visual media.
41−5%−5%0$11.2MSeries A$4M, Oct 2016
Streak transforms Gmail into a powerful CRM
40+5%+5%YC$1.9MSeed$1.9M, Oct 2012
Makes legal paperwork easy for startups and their attorneys.
34+10%+48%0SeedJun 2011
Predictive analytics and clinical pathways for hospitals
200%+11%0$2MSeed$2M, Jun 2012
Quad is where college students get things done.
160%0%0SeedAug 2011
Marketplace for Video Production Services. We help you hire the best…
4−20%−20%0$1.1MSeed$1.1M, May 2015
Real-time. Big data. PostgreSQL
3  0$13.2MUndisclosed round$9.5M, Jan 2018
Analytics with action
1  0$2.5MSeed$1M, Feb 2014
Hyperlinking the real world.
1  0SeedAug 2011
Online auto and business insurance. (Acquired 2013)
1  0$675KSeed$675K, Dec 2012
  
An easy to integrate library for native iOS applications designed to…
  
Realtime collaborative coding
  0SeedAug 2011
Layer above Kinect.
  0$150KYC investment$150K, Aug 2011
Grocery deals.
  0$5.2MSeries A$2.6M, Aug 2013
Automate credit counseling.
  0SeedAug 2011
Javascript proxy.
  
The Phone System for Sales Teams.
  0SeedAug 2011
Server key management, VPN as a Service, Privacy VPN. Sold to…
  
Software and APIs to collect, clean, and control customer data.
  
Dubjoy translates and voice-overs your video to any language
  0SeedJul 2012
Brings dozens of SaaS's (Mailchimp, Stripe, Shopify, Salesforce,…
  
Better data structures = no DB.
  
Build and grow iOS, Android, and Web apps.
  
Facebook analytics. Acquired by Unified in January 2013.
  
Generate stories from SEC filings.
  
Sell to people nearby.
  
Public transit apps. Acquired by Apple in 2013.
  
Create & Share Product Roadmaps
  
The #1 private social network
  0SeedApr 2012
Yelp for service pros.
  
Send and print photo albums with people you love. Acquired by Lyft
  
In-video advertising.
  
Creativity at Play. Tablet toys. Acquired by Google, 2015.
  0$1.1MUndisclosed round$750K, Nov 2011
We make it easy to run databases. PostgreSQL, Redis, MongoDB,…
  

How this works

1. The roster

Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.

2. The numbers

Each company is matched to Crustdata by its website. Crustdata adds team size and its change over 6 and 12 months, open roles from job postings, reported funding, and founders' past employers.

3. The lists

Hiring the most counts distinct roles posted in the last 60 days. Growth needs 10+ people today, shrinking 20+ a year ago, so tiny teams do not top the lists. Rebuilt every week.

Built with Crustdata. Get your own API key and build your own.

The numbers on this page come from three Crustdata API calls. Crustdata tags 5,000+ companies with Y Combinator as an investor; swap the filter for any investor, industry or headcount range and track your own list, with founders' work emails one call away.

  • Company search for team size, growth and funding
  • Job search with a count by company, for who is hiring and for what
  • A watch that re-runs the search weekly and sends only what changed
# 1. every company with Y Combinator as an investor
curl https://api.crustdata.com/company/search \
  -H "authorization: Bearer $CRUSTDATA_API_KEY" \
  -H "x-api-version: 2025-11-01" \
  -d '{
    "filters": { "field": "funding.investors",
                 "type": "in", "value": ["Y Combinator"] },
    "fields": ["basic_info.name",
      "headcount.total", "headcount.growth_percent",
      "funding.total_investment_usd"],
    "limit": 100
  }'

# 2. open listings per company, last 60 days (limit 0 = counts only)
curl https://api.crustdata.com/job/search \
  -H "authorization: Bearer $CRUSTDATA_API_KEY" \
  -H "x-api-version: 2025-11-01" \
  -d '{
  "filters": { "op": "and", "conditions": [
    { "field": "company.basic_info.company_id",
      "type": "in", "value": [...] },
    { "field": "metadata.date_added",
      "type": "=>", "value": "2026-08-24" } ]},
  "limit": 0,
  "aggregations": [{ "type": "group_by",
    "field": "company.basic_info.company_id", "agg": "count" }]
}'

# 3. the same company filter as a weekly watch: POST /watch/company/search

Questions about YC S11 companies

How many YC S11 companies are there?

60 companies were in Y Combinator's Summer 2011 batch (S11); 12 are active.

Which YC S11 companies are hiring?

6 companies posted roles in the last 60 days, led by Apollo (8 roles), OneSignal (8 roles) and Sift (4 roles). 7 mark themselves as hiring on YC's directory.

Which YC S11 companies are growing fastest?

By team growth over 6 months (10+ people): MixRank (+30%), Sift (+6%) and Streak (+5%).

Which YC S11 companies raised the most?

No reported rounds after their YC batch in the last 12 months.

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