23 Y Combinator companies with a founder who worked at Scale AI 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 |
|---|---|---|---|---|---|---|---|
iMessage for Sales | S23 | 65 | +18% | +30% | 1 | ||
AI Applied Research | W24 | 62 | −2% | +5% | 0 | $17.5M | Series A$17M, Jun 2025 |
The multimodal data lab | W22 | 50 | +52% | +178% | 12 | $4.1M | Seed$4M, Nov 2022 |
An AI tutor that helps you study | S23 | 16 | 0% | 0% | 0 | $2.3M | Seed$2.3M, Jan 2025 |
AI rebuilt coding. We’re rebuilding the phone | S25 | 12 | −14% | +9% | YC | $500K | YC investment$500K, Sep 2025 |
The AI data analyst for biology labs | S25 | 11 | +83% | +83% | YC | $500K | YC investment$500K, Jul 2025 |
Manage energy cost & usage with AI for facility & sustainability teams | S23 | 10 | +11% | +11% | YC | $500K | YC investment$500K, Jan 2024 |
Advancing model capabilities for critical infrastructure | S26 | 6 | 0 | $500K | YC investment$500K, Sep 2026 | ||
Make every FDE on your team capable of moving any account forward. | S25 | 6 | YC | $500K | YC investment$500K, Sep 2025 | ||
AI powered brokerage reducing residential rental commissions in NYC… | S25 | 5 | 0% | −44% | 0 | $500K | YC investment$500K, Sep 2025 |
AEO/GEO for E-Commerce and Retail | W25 | 5 | YC | $500K | YC investment$500K, Mar 2025 | ||
AI-native credentialing and contracting for healthcare | X26 | 4 | 0 | ||||
The AI Growth Engine for Industrials | W25 | 4 | YC | ||||
AI lab in San Francisco | W22 | 4 | 0 | $2.1M | Pre-seed$2M, Jun 2022 | ||
Reason is the AI teammate for work and code. | F26 | 2 | YC | ||||
Turn any website into an MCP for your agents, in minutes | F26 | 2 | 0 | ||||
Building secure polymorphic apps | W26 | 2 | 0 | $500K | YC investment$500K, Apr 2026 | ||
Long-horizon RL environments | S25 | 2 | YC | Pre-seedSep 2025 | |||
The content engine that wins attention and drives growth. | S24 | 2 | −60% | 0 | |||
Turn user feedback to product insights | S22Acquired | 2 | 0 | SeedJun 2023 | |||
API sandboxes, built for AI agents | S26 | 1 | 0 | $500K | YC investment$500K, Dec 2025 | ||
Accelerating data analysis for research | X25Inactive | 1 | 0 | ||||
Data for audio AI | S24 | 134 | 8 | $80.5M | Series B$50M, Oct 2025 |
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
23 Y Combinator companies have a founder who worked at Scale AI; 21 are active.
3 companies posted roles in the last 60 days, led by Sieve (12 roles), David AI (8 roles) and Sendblue (1 roles). 11 mark themselves as hiring on YC's directory.
By team growth over 6 months (10+ people): Novaflow (+83%), Sieve (+52%) and Sendblue (+18%).
No reported rounds after their YC batch in the last 12 months.