Space Tech, AI Infrastructure Lead Fundraises


Want to keep track of the largest startup funding deals in 2025 with our curated list of $100 million-plus venture deals to U.S.-based companies? Check out The Crunchbase Megadeals Board.

This is a weekly feature that runs down the week’s top 10 announced funding rounds in the U.S. Check out last week’s biggest funding deal roundup here.

The first week of March was a relatively brisk period for large startup funding rounds, led by three deals of $500 million or more in the space tech and AI infrastructure sectors. In addition, we saw some good-sized deals around healthcare, neuroscience and enterprise software.

1. Sierra Space, $550M, space tech: Sierra Space, a space and defense tech company that designs and manufactures satellites, spacecraft and space subsystems, secured $550 million in equity funding led by LuminArx Capital Management. The financing sets an $8 billion valuation for the 5-year-old, Louisville, Colorado-based company.

2. (tied) Ayar Labs, $500M, AI infrastructure: Ayar Labs, a producer of co-packaged optics for use in AI infrastructure, landed $500 million in Series E funding led by Neuberger Berman. The financing sets a $3.75 billion valuation for the 11-year-old, San Jose, California-based company.

2. (tied) Vast, $500M, space tech: Long Beach, California-based Vast, a startup developing next-generation space stations, announced it has raised $500 million in fresh funding. The financing includes $300 million in Series A equity and $200 million in debt, with Balerion Space Ventures as lead investor.

4. Findhelp, $250M, care platform: Findhelp, developer of a platform to coordinate care across health systems, governments, benefits providers and other entities, secured $250 million in investment from TPG’s The Rise Fund. Founded in 2010, Austin-based Findhelp describes its mission as connecting people to help and support systems.

5. Science Corp., $230M, neurotech: Alameda, California-based Science Corp., a biotech startup focused on brain-computer interface technologies, announced it has closed on a $230 million Series C fundraise. Lightspeed Venture Partners, Khosla Ventures, Y Combinator, IQT and Quiet Capital were among the investors participating in the syndicated round.

6. Cart.com, $180M, e-commerce: Cart.com, provider of an e-commerce platform and logistics services for brands to sell across digital channels, picked up $180 million in growth equity investment. Springcoast Partners led the financing for the Houston-based company.

7. Grow Therapy, $150M, mental health care: Grow Therapy, a New York-based platform for providing mental health care, raised $150 million in Series D funding led by TCV and Goldman Sachs Growth Equity.

8. Cognito Therapeutics, $105M, neuroscience: Cambridge, Massachusetts-based Cognito Therapeutics, a developer of therapies for neurodegenerative diseases, secured $105 million in Series C funding. Morningside, IAG Capital Partners and Starbloom Capital led the financing.

9. Nominal, $80M, engineering software: Nominal, a self-described provider of tools for engineers to test and operate critical technology, picked up $80 million in new funding. Founders Fund led the financing, which set a $1 billion valuation for the Austin-based company.

10. Sage, $65M, health software: New York-based Sage, provider of a software platform for senior living and skilled nursing, raised $65 million in Series C funding led by Goldman Sachs Alternatives.

Methodology

We tracked the largest announced rounds in the Crunchbase database that were raised by U.S.-based companies for the period of Feb. 28-March 6. Although most announced rounds are represented in the database, there could be a small time lag as some rounds are reported late in the week.

Illustration: Dom Guzman

Stay up to date with recent funding rounds, acquisitions, and more with the
Crunchbase Daily.