Fusion energy startup Helion raised a $465M Series G led by Thrive Capital at a $15.5B valuation, nearly tripling the valuation from its January 2025 round (Tim De Chant/TechCrunch)

Tim De Chant / TechCrunch: Fusion energy startup Helion raised a $465M Series G led by Thrive Capital at a $15.5B valuation, nearly tripling the valuation from its January 2025 round — Helion, the fusion startup backed by Sam Altman, announced on Thursday that it had raised $465 million in a new funding round that values the company at $15.5 billion.