Synthesia Reaches $4B Valuation After $200M Series E Funding

British AI video startup Synthesia has raised a fresh $200 million in Series E funding, pushing its valuation to $4 billion — nearly double its $2.1 billion valuation from just a year ago. The round also opens the door for employees to sell part of their equity, giving long-time team members a chance to cash out while the company remains private.

Synthesia has built a strong business around AI-generated avatars that help enterprises create training and internal communications videos. Unlike many AI startups still chasing profitability, the London-based company has already crossed $100 million in annual recurring revenue (ARR), a milestone it reached in April 2025. Its customer list includes major global enterprises such as Bosch, Merck, and SAP, reflecting growing demand for scalable, AI-driven corporate training tools.

The Series E round was led by existing investor GV, with participation from several returning backers. These include Series B lead Kleiner Perkins, Series C lead Accel, Series D lead New Enterprise Associates, as well as NVentures, Air Street Capital, and PSP Growth. Alongside these existing investors, new firms are also joining the cap table, including Matt Miller’s VC firm, Evantic, and the private investment firm, Hysan.

In addition to primary funding, Synthesia is facilitating a structured secondary sale that allows employees to sell shares at the same $4 billion valuation as the Series E. This process is being handled in partnership with Nasdaq, which is acting as a private-markets facilitator rather than a public exchange. The company stressed that this does not signal an IPO but instead provides a controlled, transparent way for early employees to access liquidity.

Employee secondary sales are often arranged informally and can occur at prices above or below a company’s official valuation, which can cause friction with shareholders. By running the transaction through a coordinated framework, Synthesia aims to ensure that all sales are aligned with the Series E price while retaining oversight of the process.

That long-term growth strategy extends beyond AI-generated videos. Synthesia is now investing heavily in AI agents designed to make corporate knowledge more interactive. According to the company, these agents will allow employees to engage with internal information in a more natural, human-like way — asking questions, exploring scenarios through role-play, and receiving tailored explanations rather than passively watching videos.

Early pilots of these AI agents have reportedly delivered strong results, with customers reporting higher engagement and faster knowledge transfer than with traditional training formats. Encouraged by this feedback, Synthesia plans to make AI agents a core strategic focus, alongside continued improvements to its existing video platform.

While the company has not shared forward-looking revenue projections, it believes its tools address a growing enterprise challenge: keeping workforces up to date as skills requirements shift rapidly. “We see a rare convergence of two major shifts: a technology shift with AI agents becoming more capable, and a market shift where upskilling and internal knowledge sharing have become board-level priorities,” said Synthesia co-founder and CEO Victor Riparbelli.

Together with co-founder and COO Steffen Tjerrild, Riparbelli supported the decision to enable an employee secondary sale, ensuring staff could directly benefit from the company’s growth. Founded in 2017, Synthesia now employs more than 500 people, operates from a 20,000-square-foot headquarters in London, and maintains offices in Amsterdam, Copenhagen, Munich, New York City, and Zurich.

While coordinated secondary sales remain relatively uncommon among U.K. startups, Synthesia executives believe this approach could become more widespread as private companies stay private for longer. According to Alexandru Voica, the company’s head of corporate affairs and policy, structured, cross-border employee liquidity programs may increasingly become the norm — whether facilitated by Nasdaq or similar platforms — as late-stage startups seek to balance growth, retention, and employee rewards.