Antioch announced September 8 it has raised $32 million in a Series A round led by Greylock, with participation from A*, Category Ventures, BoxGroup and Icehouse Ventures. The funding brings total capital raised to $40.5 million in just five months. Greylock's Saam Motamedi is joining the board, according to a company blog post.
The New York-based startup builds a cloud simulation platform for testing autonomous systems and robots. Its pitch centers on calibrating high-fidelity simulations to match customer hardware, sensors and software, then running thousands of parallel evaluations for development and release validation. Early customers include Amazon's Ring and Launchpad Build AI, an AI-focused manufacturing company.
The pace of fundraising is notable even by Silicon Valley standards. Antioch closed an $8.5 million seed round in April, according to TechCrunch—barely five months before securing the Series A. That seed round, led by A* and Category Ventures, reportedly valued the company at $60 million. Before that, the startup raised $4.25 million in a pre-seed round announced in early December 2025, according to Robotics & Automation News.
SEC filings reveal the Series A offering totaled $31,999,962 from eight investors, filed under the legal entity Valoros, Inc. The first sale closed July 27, with the filing submitted August 3.
A Team of Repeat Founders
Five co-founders launched Antioch in May 2025, bringing credentials from Tesla, Meta, Google DeepMind and the startup world. Harry Mellsop worked on computer vision for Tesla Autopilot in 2022 and previously co-founded Transpose, a blockchain data company that Chainalysis acquired in 2023. Alex Langshur, who also co-founded Transpose and now serves as Antioch's chief executive, signed the SEC filing. Michael Calvey, the third Transpose co-founder, joined for what he called "round two" in a LinkedIn post.
Collin Schlager comes from Meta Reality Labs, where he focused on simulation, machine learning and hardware, according to Greylock. Colton Swingle previously worked at Google DeepMind with an emphasis on sim-to-real transfer, TechCrunch reported.
The angel investor roster for the Series A includes Shyam Sankar, Palantir's chief technology officer; Adrian Macneil, chief executive of Foxglove; and Ian Andrews, who works at NVIDIA and previously held leadership roles at Groq.
Testing in the Virtual Before the Physical
Jason Mitura, vice president of software development at Amazon and chief product officer at Ring, said in a press release that the platform's simulations "have closely matched our physical test results, including in scenarios we deliberately held out of calibration." That confidence, he added, allows the team to "move more testing and development into simulation, reducing reliance on costly physical test programs."
Jon Quick, chief executive at Launchpad Build AI, described being able to "test all of the scenarios that our systems will see in production, and edge cases that are otherwise impractical or uneconomical." Quick called the impact level a first for simulation tools, though such claims are difficult to verify independently.
Antioch targets four market segments: aerial autonomy, ground autonomy, industrial autonomy and what it calls intelligent perception. The company integrates NVIDIA's Physical AI stack, including Omniverse libraries, Isaac Sim and Isaac Lab. For cloud computing at scale, the startup partners with Nebius.
Evan Helda, head of Physical AI at Nebius, acknowledged in the press release that "simulation has the potential to be a massive unlock for Physical AI, but it remains one of the hardest parts of the stack to get right." With Nebius infrastructure, he added, Antioch is "turning simulation from a highly specialized capability into something Physical AI teams can use continuously."
The platform includes what Antioch calls Antioch Agent, an agentic workflow designed to onboard CAD and building information models, author test scenarios, run suites and iterate on autonomy stacks.
Hiring Push Ahead
The company said it is hiring across simulation, machine learning, infrastructure, graphics, go-to-market and operations roles. LinkedIn listed the company with two to ten employees as of early September, though that count likely predates the funding announcement and subsequent expansion plans.
"Software-speed innovation in the physical world will be the foundation of the next industrial revolution," Motamedi said in the press release. "We believe Antioch is building the core development platform for this next phase of physical AI."
Whether that ambitious vision materializes remains to be seen, but the investor appetite suggests the market sees promise in making robotics development less dependent on expensive real-world testing cycles.
