19 Y Combinator companies with a founder who worked at Blackstone before.
Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.
| Company | Batch | Team | 6 mo | 12 mo | Open roles | Total raised | Last round |
|---|---|---|---|---|---|---|---|
Modern insurance brokerage. | W18Acquired | 542 | −11% | −18% | 0 | $310M | Series D$200M, Apr 2022 |
Marketplace for employers to recruit college students and recent grads | W15Acquired | 96 | +7% | +9% | 0 | $37.3M | Private equity$10M, Oct 2018 |
AI Operating System for Private Market Investors | S23 | 36 | −3% | +29% | 1 | $3M | Seed$3M, Feb 2024 |
Your personalised benefits and engagement platform for global teams | W22 | 36 | +64% | +64% | YC | $16.6M | Grant$11M, Sep 2026 |
The AI-Native Turnkey Alternative Investment Platform (TAIP) | S21 | 29 | +93% | +142% | YC | $18.9M | Series A$15M, Sep 2026 |
Neural interfaces to understand and use nerve data in medicine. | W17 | 23 | −8% | −8% | 0 | $46.8M | Undisclosed round$20M, Jan 2024 |
We help security, legal and sales teams answer customer questions | S22 | 17 | +13% | +183% | 0 | Pre-seedAug 2022 | |
AI-powered market due diligence for investment decisions | F25 | 13 | +44% | +160% | 6 | $5.5M | Seed$5M, Mar 2026 |
Fig adds visual apps, shortcuts, and autocomplete to your terminal. | S20Acquired | 10 | −9% | 0 | $2.4M | Seed$2.2M, Aug 2021 | |
Estate settlement, from verified discovery to distribution | S24 | 8 | −11% | +14% | YC | $500K | YC investment$500K, Sep 2024 |
Real-time governance for enterprise communications | F24 | 6 | 0% | −14% | YC | $500K | YC investment$500K, Jan 2025 |
We audit medical claims for self-insured employers and health plans. | S25 | 4 | 0 | $500K | YC investment$500K, Jun 2025 | ||
Vercel For GPUs | W25Acquired | 4 | 0 | $500K | YC investment$500K, Mar 2025 | ||
Helping Startups Grow Organically | S24 | 4 | −78% | YC | |||
The Fastest Multimodal Inference OS | W26 | 2 | YC | $500K | YC investment$500K, Apr 2026 | ||
Agent teams for complex work | W25 | 2 | 0 | $500K | YC investment$500K, Feb 2025 | ||
Agents for quantitative research and financial data science. | S24 | 2 | 0 | ||||
AI Analysts for the Buy-Side | W23 | 1 | 0 | Pre-seedApr 2023 | |||
Lead intelligence as a service. We want to be your personal lead… | W14Acquired | 0 | $120K | YC investment$120K, Mar 2014 |
Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.
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.
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.
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.
# 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
19 Y Combinator companies have a founder who worked at Blackstone; 14 are active.
2 companies posted roles in the last 60 days, led by DiligenceSquared (6 roles) and VectorShift (1 roles). 8 mark themselves as hiring on YC's directory.
By team growth over 6 months (10+ people): Aqua (+93%), Happl (+64%) and DiligenceSquared (+44%).
Largest latest rounds in the last 12 months, after their YC batch: Aqua ($15M) and DiligenceSquared ($5M).