Stealth Startup Spy #245 - Y Combinator X25
The Y Combinator X25 Demo Day is around the corner! Here's a final look at the full YCX25 batch.
Demo Day is here (Wednesday, June 11th) and we’ve taken a closer look at YC’s Spring 2025 batch: 144 companies and 307 founders.
Here’s the full look at the Y Combinator Spring 2025 batch.
From AI tools to space tech to next-gen bio, there’s plenty to keep an eye on this batch. But what really stands out is the caliber of founders - many coming from OpenAI, Meta, Stripe, NASA, Brex, and beyond.
Here are a few that caught our attention:
1. Automating Work for Knowledge Teams
Odapt - Build AI-powered internal tools with just plain language.
Team: Ex-McKinsey analyst + OpenAI engineer + ex-Facebook research engineerCombinely - AI coworker for accountants to streamline complex workflows.
Team: Ex-Google software engineer + former Deloitte accountantBeluga Labs - Rippling for creators: AI-powered finances and automated taxes in one platform.
Team: Harvard grads and HubSpot, Meta, Bubble alumSieve - Data cleaning platform delivering clean, reliable data via APIs and Excel for hedge funds.
Team: MIT grads, ex-Bain Associate Consultant and McKinsey Business AnalystDocket - AI agents for web testing
Team: Former engineers from Meta, Citadel, Stripe, Brex, AWS, Patreon, and GitHub
2. Building the Future of Infra & Dev Platforms
Klavis - Open-source MCP integration layer for AI apps.
Team: Ex-Google DeepMind ML engineer + ex-Lyft backend leadCasco - Evaluate AI agents and apps on security, safety, and accuracy.
Team: Ex-AWS Head of Product + Ex-Microsoft Program Manager
3. Deep Tech for Physical Systems
Partcl - Accelerating chip design with AI-powered EDA tools.
Team: Stanford EE PhDs + ex-NVIDIA, Apple, and Amazon hardware engineers
Cascade Space - Deep space communications as a service
Team: Ex-SpaceX RF lead + former Astra mission systems PM + Zoox systems engineer
Zeon Systems - AI-powered robotics for scientific lab automation.
Team: Ex-LatchBio bioinformatics leads with degrees from Yale, UC Berkeley, and IIT
4. Bio & Material Innovation
Bramante Biologics — Protein design platform for next-gen biomaterials.
Team: UPenn PhD in Bioengineering + Yale Math alum, ex-McKinsey and Protein Evolution co-founder
Today’s the last day to get early access > Download Full YC X25 Batch List
FYI - This data set contains Founder Names, Job Title, FounderDNA, Email, Company, Website, Descriptions, and much more.
We’ve tracked everything through stealth mode announcements, pivots, name changes and rebrands making this the most complete data set of YC X25 batch founders.
Get access to all of the founders and companies before demo day!
Looks like we’ve already picked up 11+ founders who have been accepted into YC’s Summer 2025 batch. More on this in future newsletter issues…
Stay Stealthy,
Drake
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