RaiseTrack

Reactor Series A (2026)

Reactor raised an undisclosed amount in a Series A round, announced on 2026-05-28. The round was led by Lightspeed Venture Partners.

Company
Reactor
Round type
Series A
Date
2026-05-28
Industry
AI infrastructure, real-time generative video and world models
Location
San Francisco, CA

Summary

Lightspeed announced on 2026-05-28 that it was leading Reactor's Series A, after co-leading the seed, with $59 million in combined funding across both rounds. On 2026-10-05 Reactor announced that NVIDIA and Sapphire Ventures had joined the Series A. The Series A amount on its own is not disclosed. FinSMEs also names WndrCo, Amplify Partners, Sky9 Capital and FPV Ventures. Because FinSMEs describes all investors as leads, while the other sources name only Lightspeed as lead, those four are listed without a role.

Investors

Lead

Participating

Sources

Last verified:

  1. https://lsvp.com/stories/the-developer-platform-for-world-models-our-series-a-in-reactor/
    Type: official investor website. Accessed 2026-10-06.
    Lightspeed post dated 2026-05-28. Says Lightspeed is leading the Series A after co-leading the seed, $59M in combined funding, and names co-founders Alberto Taiuti and Bryce Schmidtchen.
  2. https://markets.financialcontent.com/stocks/article/bizwire-2026-10-5-reactor-expands-investors-in-series-a-round-to-scale-real-time-world-model-infrastructure
    Type: funding announcement. Accessed 2026-10-06.
    Business Wire release dated 2026-10-05, read on FinancialContent. Says NVIDIA and Sapphire Ventures joined the Series A led by Lightspeed Venture Partners.
  3. https://www.finsmes.com/2026/10/reactor-closes-series-a-funding.html
    Type: reputable publication. Accessed 2026-10-06.
    FinSMEs article dated 2026-10-06. Source of the San Francisco, CA location. Calls the amount undisclosed and lists Lightspeed, WndrCo, Amplify Partners, Sky9 Capital, FPV Ventures, NVIDIA and Sapphire Ventures together as leading the round.