Stealth Startup Spy #243 - Y Combinator X25
An early look at the Y Combinator Spring 2025 batch a week before demo day! Full list available for download.
Y Combinator’s Spring 2025 Batch (YC X25) Demo Day is next week. (Wednesday, June 11th)
We’ve picked up just under 145 companies (305 founders) in this batch with a few still remaining in stealth. Here’s the full look at the Y Combinator Spring 2025 batch.
140+ total companies
94 are AI-related → That’s 66% of the batch.
101 are B2B → Still the dominant model by far.
San Francisco still rules: 92 companies are based there (64% of the batch)
Remote is nearly nonexistent unlike in prior batches (IRL is back!)
A few global players (Paris, Cambridge) are sprinkled in
We’ve already seen some impressive demos from this Spring batch. Below are the most promising startups and why they stand out:
Godela
What they do: AI Physics Engine
Why we like it: This isn’t your average SaaS wrapper. An AI-native physics engine has enormous implications across simulation, robotics, gaming, and digital twin tech. If real, this could be foundational infrastructure for the next wave of embodied AI.
SAVA
What they do: Sheet Metal Super Factory
Why we like it: YC rarely bets on hard industrial businesses and this is a bold exception. If SAVA can digitize and scale a messy, capital-intensive vertical like sheet metal, it could be a Flexport-style breakout in advanced manufacturing.
MindFort
What they do: Autonomous offensive security agents & malware simulators
Why we like it: This startup feels like a sneak peek into the future of red-teaming. Imagine spinning up smart, evolving AI attackers to probe your own systems before real threats do. Catnip for enterprise CISOs.
Vesence
What they do: Cursor for Lawyers. Agentic AI in MS Office.
Why we like it: This is a classic “AI for professionals” wedge but with a twist. Embedding legal-focused AI agents directly in Microsoft Office puts them in the workflow of every law firm and in-house counsel team. Quietly massive TAM.
Delty
What they do: AI staff engineer that designs systems and guides juniors
Why we like it: Every dev org dreams of cloning their 10x engineer. Delty’s trying to do it. If they nail even 60% of this promise, they'll instantly unlock productivity and onboarding at scale across technical teams.
Janus
What they do: Battle-Test AI Agents with Human Simulation
Why we like it: Janus builds simulated environments to stress-test agentic systems (think of it as a war room for AI). As autonomous agents become more complex, tools like this will be mission-critical for debugging, reliability, and safety.
Airweave
What they do: Open-source tool that lets agents search any app
Why we like it: This feels like the “Zapier for agents.” If AI agents are going to work across your software stack, they’ll need this kind of universal interface layer. Open-source and infrastructure-first gives it serious platform potential.
Third Chair
What they do: Agents for in-house legal teams
Why we like it: Legal tech is notoriously slow to modernize, but the wedge here is perfect - an agent that quietly sits beside in-house teams, handling doc review, contract redlines, and legal research. Boring? Maybe. Lucrative? Definitely.
Daxa
What they do: Boost revenue and retention with an AI PM
Why we like it: Daxa positions itself as an “AI product manager”, essentially a co-pilot for growth. It’s a bold positioning, but if it can actually connect data to decisions and outcomes, every startup with a product team will want it.
Scalar Field
What they do: Reinventing the trading terminal, one intelligent chart at a time
Why we like it: The trading terminal hasn’t changed in decades. If Scalar Field brings intelligent overlays, real-time agent insights, or AI-native UI/UX to capital markets, it could quietly disrupt how traders and analysts interact with data.
Last chance 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 track every stealth move, pivot, and rebrand to bring you the most complete YC X25 founder data out there.
If you are one of the 11 investors who got early access to this list, filter the “Date Added” column to see all the new changes.
Get access to all of the founders and companies before demo day next week!
Looks like we’ve already picked up 10+ 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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