U.S. startups closed more than a dozen funding rounds in the hundreds of millions this week, led by Ramp's $750 million raise for spend-management software.

Ramp, a New York-based spend-management software provider, raised $750 million led by Iconiq, GIC, and Ontario Teachers' Pension Plan, reaching a $44 billion valuation.

Three startups each closed $500 million rounds: Impulse Space (spacecraft and propulsion systems), Supabase (open source platform for developers and AI app builders), and Flourish (artificial intelligence models inspired by the human brain).

Other major rounds included Helion at $465 million for fusion energy, NewLimit at $435 million for longevity medicines, Suno and Generalist AI each at $400 million for AI music tools and AI-enabled robotics respectively, AlphaSense at $350 million for AI market intelligence, and Mach Industries at $300 million for defense technology.