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X25 companies that raised the most in the last 12 months

The 19 YC X25 companies whose latest reported round, after their YC batch and in the last 12 months, was the largest.

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

Showing 19 of 19 companies on this list
#CompanyTeam6 mo12 moOpen rolesTotal raisedLast round
1
quantum-accelerated AI servers
48+50%+118%8$139MSeries A$105M, Mar 2026
2
Autonomous Company Infrastructure
15+150%+200%3$28.5MSeries A$28.5M, Aug 2026
3
We supply hard tech companies with critical components.
6+20% YC$25MSeed$25M, Jul 2026
4
The agentic operating system for modern system integrators.
48+37%+167%3$20.5MSeries A$20M, Apr 2026
5
Function Health for Europe
44+26%+100%3$28.5MSeries A$20M, May 2026
6
Autonomous security testing for web apps, APIs, cloud, and AI systems
21+75%+200%YC$17.2MSeries A$13M, Jul 2026
7
Secure internal apps. Built by AI in seconds. Powered by your data.
14+27%+56%0$10.5MSeed$10M, Dec 2025
8
24/7 Global Stock Exchange
12+50%+50%YC$10MSeed$9.5M, Mar 2026
9
Industrial data layer for physical RSI
56+331% 0$7.6MSeed$6M, Jun 2026
10
Software to monitor, control, and optimize data centers.
13+30%+63%YC$5.1MSeed$5.1M, Dec 2025
11
Design a chip in minutes
7  YC$5MSeed$5M, Apr 2026
12
Agentic AI platform for Pharma GTM teams
39+63%+144%YC$5MSeed$5M, Nov 2025
13
AI Revenue Platform for Post-Acute Care
13+63%+160%3$4.9MSeed$4.4M, Jan 2026
14
Play the latest games in your browser with no downloads
9 +29%0$4.3MSeed$3.8M, Dec 2025
15
Voice data for AI
18+13%+260%YC$3.5MSeed$3M, Nov 2025
16
Agent-native GitHub Actions runners
3  0$3.5MPre-seed$3M, Sep 2026
17
AI-Native Mortgage Broker
6−25%−14%YC$2.9MSeed$2.9M, Jun 2026
18
The AI Associate for Litigation Lawyers
33−3%−11%0$3MSeed$2.5M, May 2026
19
Product Native Models
4−20%−33%0$2.5MSeed$2M, Nov 2025

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 X25 companies

How many YC X25 companies are there?

144 companies were in Y Combinator's Spring 2025 batch (X25); 136 are active.

Which YC X25 companies are hiring?

11 companies posted roles in the last 60 days, led by Sygaldry Technologies (8 roles), Sim (4 roles) and Lucis (3 roles). 57 mark themselves as hiring on YC's directory.

Which YC X25 companies are growing fastest?

By team growth over 6 months (10+ people): Linewise (+331%), Naïve (+150%) and Sixtyfour (+117%).

Which YC X25 companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: Sygaldry Technologies ($105M), Naïve ($28.5M) and Foundation Industries ($25M).

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