ZAP Surgical raises $36M led by Catalio after its 50th ZAP-X radiosurgery robot ships

ZAP Surgical Systems, the San Carlos, California maker of the ZAP-X brain radiosurgery robot, said in a press release on Oct 19 that it has raised $36 million in a financing led by Catalio Capital Management, with continued support from Baheal, its strategic partner in China. The company did not name a series or disclose a valuation. [Company profile](/companies/zap-surgical).

The money arrives just after a commercial threshold. ZAP said it has shipped its 50th ZAP-X system and is scaling production capacity, and that nearly 10,000 patients have been treated on the platform worldwide. That is roughly 200 patients per shipped system by MEKAWIRE's arithmetic (10,000 / 50), a crude ratio because shipped systems are not all in clinical use yet. Catalio, a New York healthcare and AI investor with more than $2 billion under management, gets a board observer seat for Nicholas von Guionneau.

What the money is for, as the company states it

ZAP said the capital will fund global expansion of ZAP-X into academic medical centres, community hospitals and physician-led practices. Founder and chief executive John Adler, the Stanford neurosurgeon who invented the CyberKnife, said Catalio would help accelerate adoption in the United States while Baheal has driven the China business. The release also points to a second bet: "radiomodulation", low-dose targeted radiation aimed at psychiatric disorders. ZAP said a first-in-human pilot in severe treatment-resistant depression produced encouraging preliminary data and that multi-centre trials, starting with depression and addiction, are being planned. Those trials have no dates yet.

ZAP-X is a self-shielded, linear-accelerator system on a gyroscopic gantry, so it needs no radiation bunker and no cobalt source. It received FDA 510(k) clearance in 2017, Japanese Shonin approval in 2020 and the EU CE mark in 2021, according to the company. Recent newsroom items cover first installations in Australia (Sept 8) and Thailand (Sept 22), an eighth system in China (Aug 5) and a programme at Fukuoka Kieikai Hospital in Japan (Oct 1).

The round is less than half the last one

ZAP's previous disclosed round was a $78 million Series E led by Qingdao Baheal Medical, announced on Nov 8, 2024. The new $36 million is 46% of that, 710 days (about 23 months) later, and the two disclosed rounds add up to $114 million. Earlier rounds are not in MEKAWIRE's verified data, so this is not a lifetime total.

Against surgical robotics peers in our database, the round is mid-sized. It is 24% of Distalmotion's $150 million Series G (November 2025) and 65% of Moon Surgical's $55.4 million (May 2023), and far below the roughly $400 million Stryker put into CMR Surgical this month with an option to buy it.