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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.

Startup investors this week demonstrated continued willingness to write big checks for promising companies in sought-after areas. Leading the pack was , an AI identity security platform that picked up a fresh $700 million.

The next three largest rounds — , and — all shared some focus on energy. The rest of the list included companies in AI, biotech and space tech.

1. , $700M, AI identity security: Saviynt, a provider of AI-optimized identity security tools, that it secured $700 million in Series B financing. led the round, which set a $3 billion valuation for the 15-year-old, El Segundo, California-based company.

2. , $475M, AI energy efficiency: Unconventional AI, a startup designing a computer to optimize energy efficiency for AI, raised $475 million in seed funding. and led the financing for the San Francisco Bay Area company.

3. , $462M, geothermal energy: Houston-based Fervo Energy, a developer and operator of geothermal energy projects with a focus on technologies to scale this power source, $462 million in Series E funding led by . The funding will go toward a geothermal project in Western Utah as well as other projects in its pipeline.

4. , $300M, fast airplanes, turbines: Boom Supersonic, a Denver company working to build what it says will be the world’s fastest airliner, $300 million led by . In addition to its planes, Boom is also attracting investor interest for its Superpower natural gas turbine that can also have applications in delivering energy to AI data centers.

5. , $250M, space tech: Torrance, California-based K2 Space, developer of a platform for building large, high-power satellites, landed $250 million in Series C funding. led the round, which set a $3 billion valuation for the company, which was founded in 2022.

6. , $240M, software development: Harness, a developer of tools to automate and simplify software delivery processes, raised $200 million in Series E funding and $40 million in a planned tender to provide liquidity to long-term employees. led the Series E, which set a $5.5 billion valuation for the 8-year-old company.

7. , $158M, medical devices: Marlton, New Jersey-based Impulse Dynamics, a medical device company focused on patients with heart failure, secured over $158 million in a funding round led by and . The financing follows an announcement from the extending coverage for its device.

8. , $140M, generative AI: Fal, developer of a real-time generative AI platform for video, images, 3D and audio, picked up $140 million in a Series D financing Led by . The round was the third this year for San Francisco-based Fal, which closed a Series C in July and a Series B in February.

9. , $110M, biotech: Sanegene Bio, a biotech startup focused on developing RNAi-based therapeutics, said it raised over $110 million in Series B funding from a long list of venture investors. Founded in 2021, the startup is headquartered in Boston with significant operations in China.

10. , $84M, biotech: San Diego-based BlossomHill Therapeutics, a developer of medicines to treat cancer, pulled in $84 million in Series B extension funding. , and led the financing for the 5-year-old company.

Methodology

We tracked the largest announced rounds in the ¸½½üÉÏÃÅ database that were raised by U.S.-based companies for the period of Dec. 6-12. 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.

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